It is currently 21 Oct 2017, 23:48

### GMAT Club Daily Prep

#### Thank you for using the timer - this advanced tool can estimate your performance and suggest more practice questions. We have subscribed you to Daily Prep Questions via email.

Customized
for You

we will pick new questions that match your level based on your Timer History

Track

every week, we’ll send you an estimated GMAT score based on your performance

Practice
Pays

we will pick new questions that match your level based on your Timer History

# Events & Promotions

###### Events & Promotions in June
Open Detailed Calendar

# The popular notion that a tree's age can be determined by

Author Message
TAGS:

### Hide Tags

Director
Joined: 24 Aug 2006
Posts: 743

Kudos [?]: 203 [3], given: 0

Location: Dallas, Texas
The popular notion that a tree's age can be determined by [#permalink]

### Show Tags

07 Dec 2006, 20:27
3
KUDOS
18
This post was
BOOKMARKED
00:00

Difficulty:

55% (hard)

Question Stats:

60% (01:17) correct 40% (01:26) wrong based on 781 sessions

### HideShow timer Statistics

The popular notion that a tree's age can be determined by counting the number of internal rings in its trunk is generally true. However, to help regulate the internal temperature of the tree, the outermost layers of wood of the Brazilian ash often peel away when the temperature exceeds 95 degrees Fahrenheit, leaving the tree with fewer rings than it would otherwise have. So if the temperature in the Brazilian ash's environment never exceeded 95 degrees Fahrenheit, its rings would be a reliable measure of the tree's age.

Which of the following is an assumption on which the argument above depends?
(A) The growth of new rings in a tree is not a function of levels of precipitation.
(B) Only the Brazilian ash loses rings because of excessive heat.
(C) Only one day of temperatures above 95 degrees Fahrenheit is needed to cause the Brazilian ash to lose a ring.
(D) The internal rings of all trees are of uniform thickness.
(E) The number of rings that will be lost when the temperature exceeds 95 degrees Fahrenheit is not predictable
[Reveal] Spoiler: OA

_________________

"Education is what remains when one has forgotten everything he learned in school."

Last edited by Nevernevergiveup on 24 Apr 2016, 00:10, edited 1 time in total.

Kudos [?]: 203 [3], given: 0

Director
Joined: 12 Jun 2006
Posts: 532

Kudos [?]: 162 [0], given: 1

Re: The popular notion that a tree's age can be determined by [#permalink]

### Show Tags

07 Dec 2006, 20:53
Quote:
The popular notion that a tree's age can be determined by counting the number of internal rings in its trunk is generally true. However, to help regulate the internal temperature of the tree, the outermost layers of wood of the Brazilian ash often peel away when the temperature exceeds 95 degrees Fahrenheit, leaving the tree with fewer rings than it would otherwise have. So if the temperature in the Brazilian ash's environment never exceeded 95 degrees Fahrenheit, its rings would be a reliable measure of the tree's age.

Which of the following is an assumption on which the argument above depends?
(A) The growth of new rings in a tree is not a function of levels of precipitation.
(B) Only the Brazilian ash loses rings because of excessive heat.
(C) Only one day of temperatures above 95 degrees Fahrenheit is needed to cause the Brazilian ash to lose a ring.
(D) The internal rings of all trees are of uniform thickness.
(E) The number of rings that will be lost when the temperature exceeds 95 degrees Fahrenheit is not predictable

No mention is made of ring thickness. D is out.

We are asked "So if the temperature in the Brazilian ash's environment never exceeded 95 degrees Fahrenheit, its rings would be a reliable measure of the tree's age?" C and E discuss the environment temperature exceeding 95 degrees. C and E are out.

If B had said something like "The Brazilian Ash is representative of all trees" I'd go with B. B, as it's stated, weakens the argument. B is out.

I'd have to go with A. .... me thinks

Kudos [?]: 162 [0], given: 1

Manager
Joined: 01 Oct 2006
Posts: 240

Kudos [?]: 14 [0], given: 0

Re: The popular notion that a tree's age can be determined by [#permalink]

### Show Tags

07 Dec 2006, 20:59
1
This post was
BOOKMARKED
Swagatalakshmi wrote:
The popular notion that a tree's age can be determined by counting the number of internal rings in its trunk is generally true. However, to help regulate the internal temperature of the tree, the outermost layers of wood of the Brazilian ash often peel away when the temperature exceeds 95 degrees Fahrenheit, leaving the tree with fewer rings than it would otherwise have. So if the temperature in the Brazilian ash's environment never exceeded 95 degrees Fahrenheit, its rings would be a reliable measure of the tree's age.

Which of the following is an assumption on which the argument above depends?
(A) The growth of new rings in a tree is not a function of levels of precipitation.
(B) Only the Brazilian ash loses rings because of excessive heat.
(C) Only one day of temperatures above 95 degrees Fahrenheit is needed to cause the Brazilian ash to lose a ring.
(D) The internal rings of all trees are of uniform thickness.
(E) The number of rings that will be lost when the temperature exceeds 95 degrees Fahrenheit is not predictable

I am somewhere among A, C and E

In E: Probably it does not matter whether we know the the number of rings lost when temperature exceeds 95 degrees. If we knew, say, teh tree loses 1 ring when the temp exceeds 95 degrees. we do not know how many days was the temperature over 95 degrees during the tree's lifetime (since we do not know tree's ag eto begin with)

A: I don't think we are really concerned about how the rings grow. The concern is how the rings can decrease

By POE, C seems to be the choice though it is a little strong because of the usage of only.

The information in the paragraph says: So if the temperature in the Brazilian ash's environment never exceeded 95 degrees Fahrenheit, its rings would be a reliable measure of the tree's age. Usage of never seems to indicate that if the temperature is over 95 degrees on even 1 day, then the tree should at least lose 1 ring.

Kudos [?]: 14 [0], given: 0

Manager
Joined: 25 Sep 2006
Posts: 150

Kudos [?]: 7 [0], given: 0

Re: The popular notion that a tree's age can be determined by [#permalink]

### Show Tags

07 Dec 2006, 21:00
I say E

The passage says that <95 degree, the rings would be a reliable measure. It must have assumed E
_________________

livin in a prison island...

Kudos [?]: 7 [0], given: 0

SVP
Joined: 08 Nov 2006
Posts: 1552

Kudos [?]: 204 [0], given: 1

Location: Ann Arbor
Schools: Ross '10
Re: The popular notion that a tree's age can be determined by [#permalink]

### Show Tags

07 Dec 2006, 23:04
I like A.

The passage says that the number of rings is affected by temperature and that if the tempearatures do not reach the 95 deg, then the rings are an accurate measure of the life of the tree.

This will be true only if there are no other factors that affect ring growth/ring shed.

If A (The growth of new rings in a tree is not a function of levels of precipitation)is false, then this argument will not hold water. So A has to be true.

So A must be the assumption.

Kudos [?]: 204 [0], given: 1

Director
Joined: 06 Feb 2006
Posts: 893

Kudos [?]: 123 [0], given: 0

Re: The popular notion that a tree's age can be determined by [#permalink]

### Show Tags

08 Dec 2006, 03:16
I say E...

A is out of scope.....

Argument says that it is impossible to determine the age of the Brazilian ash if the temperature exceeds 95 F, because the tree peels away some layers of wood... And the number of layers of wood is an indication of age....

Thus it is assumed that there is no way to calculate the number of layers the tree will loose in high temperatures....

Kudos [?]: 123 [0], given: 0

Director
Joined: 28 Dec 2005
Posts: 915

Kudos [?]: 57 [0], given: 0

Re: The popular notion that a tree's age can be determined by [#permalink]

### Show Tags

08 Dec 2006, 04:06
Another E for me. The author states that the Brazilian ash age can be reliably measured when temperature never went above 95, implying that it cannot be reliably measured otherwise.

Editing:

I am now going towards A. The conclusion says: So if the temperature in the Brazilian ash's environment never exceeded 95 degrees Fahrenheit, its rings would be a reliable measure of the tree's age.

The conclusion is all about how reliable it is to estimate age when temp is below 95. So A comes up as an assumption.

I am learning (slowly) not to look into what the author is trying to imply, or what I think the author is trying to imply, but take the sentence at face value.

Last edited by mbagal1 on 08 Dec 2006, 11:49, edited 2 times in total.

Kudos [?]: 57 [0], given: 0

Senior Manager
Joined: 17 Aug 2005
Posts: 387

Kudos [?]: 140 [0], given: 0

Location: Boston, MA
Re: The popular notion that a tree's age can be determined by [#permalink]

### Show Tags

08 Dec 2006, 07:40
Quote:
I like A.

The passage says that the number of rings is affected by temperature and that if the tempearatures do not reach the 95 deg, then the rings are an accurate measure of the life of the tree.

This will be true only if there are no other factors that affect ring growth/ring shed.

If A (The growth of new rings in a tree is not a function of levels of precipitation)is false, then this argument will not hold water. So A has to be true.

So A must be the assumption.

exactly my thoughts, ncprasad. A for me too.

Kudos [?]: 140 [0], given: 0

Director
Joined: 24 Aug 2006
Posts: 743

Kudos [?]: 203 [0], given: 0

Location: Dallas, Texas
Re: The popular notion that a tree's age can be determined by [#permalink]

### Show Tags

08 Dec 2006, 19:17
hmmm .... 6/6 split between A and E ... I was with E but the OA is A.
_________________

"Education is what remains when one has forgotten everything he learned in school."

Kudos [?]: 203 [0], given: 0

Director
Joined: 12 Jun 2006
Posts: 532

Kudos [?]: 162 [0], given: 1

Re: The popular notion that a tree's age can be determined by [#permalink]

### Show Tags

08 Dec 2006, 22:08
Swagatalakshmi,

Can we have the OR (official reasoning)?

Kudos [?]: 162 [0], given: 1

Director
Joined: 24 Aug 2006
Posts: 743

Kudos [?]: 203 [0], given: 0

Location: Dallas, Texas
Re: The popular notion that a tree's age can be determined by [#permalink]

### Show Tags

09 Dec 2006, 22:40
I don't have OE.
_________________

"Education is what remains when one has forgotten everything he learned in school."

Kudos [?]: 203 [0], given: 0

SVP
Joined: 03 Jan 2005
Posts: 2231

Kudos [?]: 377 [0], given: 0

Re: The popular notion that a tree's age can be determined by [#permalink]

### Show Tags

10 Dec 2006, 22:50
Swagatalakshmi wrote:
The popular notion that a tree's age can be determined by counting the number of internal rings in its trunk is generally true. However, to help regulate the internal temperature of the tree, the outermost layers of wood of the Brazilian ash often peel away when the temperature exceeds 95 degrees Fahrenheit, leaving the tree with fewer rings than it would otherwise have. So if the temperature in the Brazilian ash's environment never exceeded 95 degrees Fahrenheit, its rings would be a reliable measure of the tree's age.

Argument1: TreeAge<=NumberOfRings
Argument2: If Temp>95, TreeAge<=NumberOfRings
Conclusion: If Temp<=95, TreeAge=NumberOfRings

Assumption needed would be there is no other factors that will cause less number of rings other than temp>95.

Compare this to the following options, A is remotely possible because it talks about precipitation not being a factor that determines number of rings. B through E are irrelevent. A isn't the best answer, in my opinion, but is the only possible one in the choices given.
_________________

Keep on asking, and it will be given you;
keep on seeking, and you will find;
keep on knocking, and it will be opened to you.

Kudos [?]: 377 [0], given: 0

Intern
Joined: 07 Dec 2006
Posts: 13

Kudos [?]: [0], given: 0

Re: The popular notion that a tree's age can be determined by [#permalink]

### Show Tags

04 Jan 2007, 12:12
I'm going with F, none of the above.

The conclusion states that the tree's age can be reliably determined by the rings. An approiate assumption would be:
The "Brazilian ash" grows at a rate that is consistent with other trees, whose age can be determined by the number of rings in it's trunk".

Bringing precipitation into the equation is out of scope.

IMO, this is a garbage question.

Kudos [?]: [0], given: 0

Senior Manager
Joined: 04 Nov 2006
Posts: 258

Kudos [?]: 245 [0], given: 0

Location: California
Re: The popular notion that a tree's age can be determined by [#permalink]

### Show Tags

04 Jan 2007, 14:25
also, if u apply the idea of negation.. E comes out good.. if you can predict rings lost due to temp, then arguments does not hold...

i think A is talking about the growth of rings, not the decrease.. so it should anyways not work..

OA is wrong..

Kudos [?]: 245 [0], given: 0

Senior Manager
Joined: 17 Aug 2005
Posts: 387

Kudos [?]: 140 [0], given: 0

Location: Boston, MA
Re: The popular notion that a tree's age can be determined by [#permalink]

### Show Tags

06 Jan 2007, 10:49
I disagree. I stand by A, here's why:

The arguments conclusion is that if the temperature NEVER gets above 95 degrees then the number of rings is an accurace prediction of the tree's age.

(E) says that:
The number of rings that will be lost when the temperature exceeds 95 degrees Fahrenheit is not predictable

No one cares about what happens when the temp gets over 95 degrees, the arguments scope is only below 95 degrees.

A is right because if there is another factor that the author did not consider in predicting the tree's age -- PRECIPITATION -- then the argument falls apart and this has to be our assumption.

Its not a great question IMO, but I stick to my guns with A.

Kudos [?]: 140 [0], given: 0

Director
Joined: 26 Feb 2006
Posts: 900

Kudos [?]: 157 [0], given: 0

Re: The popular notion that a tree's age can be determined by [#permalink]

### Show Tags

06 Jan 2007, 12:57
Swagatalakshmi wrote:
The popular notion that a tree's age can be determined by counting the number of internal rings in its trunk is generally true. However, to help regulate the internal temperature of the tree, the outermost layers of wood of the Brazilian ash often peel away when the temperature exceeds 95 degrees Fahrenheit, leaving the tree with fewer rings than it would otherwise have. So if the temperature in the Brazilian ash's environment never exceeded 95 degrees Fahrenheit, its rings would be a reliable measure of the tree's age.

Which of the following is an assumption on which the argument above depends?

(A) The growth of new rings in a tree is not a function of levels of precipitation.
(B) Only the Brazilian ash loses rings because of excessive heat.
(C) Only one day of temperatures above 95 degrees Fahrenheit is needed to cause the Brazilian ash to lose a ring.
(D) The internal rings of all trees are of uniform thickness.
(E) The number of rings that will be lost when the temperature exceeds 95 degrees Fahrenheit is not predictable

A and E both seem correct but still a bit confusing........

A. If more percipatation => more rings. then age of the tree according to the rings is misleading because the tree has one ring/year. therefore, percipatation shouldnot cause to have more rings.

E. if we know the number of rings lost due to the tempreture that exceeds 95 degrees fahrenheight, then still we can identify the age of the tree and the lost rings have no effect in finding the age of the tree. so if temp>95 and we donot know the lost rings, it is not possible to find the age of the tree. otherwise, yes. the passage says that if there were no temp >95, the no of rings are reliable measure of tree's age. even if there were temp>95 and we donot know the lost rings because of temp>95, then the no of rings are not reasonable measure of the tree's age.

Kudos [?]: 157 [0], given: 0

Director
Affiliations: FRM Charter holder
Joined: 02 Dec 2006
Posts: 726

Kudos [?]: 96 [0], given: 4

Schools: Stanford, Chicago Booth, Babson College
Re: The popular notion that a tree's age can be determined by [#permalink]

### Show Tags

07 Jan 2007, 06:09
If the number of rings that will be lost when the temperature exceeds 95 degrees Fahrenheit is predictable, then tree's age can be determined by counting the number of internal rings.

Hence, I think the anwer is E.

Kudos [?]: 96 [0], given: 4

Senior Manager
Joined: 24 Nov 2006
Posts: 349

Kudos [?]: 27 [0], given: 0

Re: The popular notion that a tree's age can be determined by [#permalink]

### Show Tags

07 Jan 2007, 09:34
Swagatalakshmi wrote:
The popular notion that a tree's age can be determined by counting the number of internal rings in its trunk is generally true. However, to help regulate the internal temperature of the tree, the outermost layers of wood of the Brazilian ash often peel away when the temperature exceeds 95 degrees Fahrenheit, leaving the tree with fewer rings than it would otherwise have. So if the temperature in the Brazilian ash's environment never exceeded 95 degrees Fahrenheit, its rings would be a reliable measure of the tree's age.

Which of the following is an assumption on which the argument above depends?
(A) The growth of new rings in a tree is not a function of levels of precipitation.
(B) Only the Brazilian ash loses rings because of excessive heat.
(C) Only one day of temperatures above 95 degrees Fahrenheit is needed to cause the Brazilian ash to lose a ring.
(D) The internal rings of all trees are of uniform thickness.
(E) The number of rings that will be lost when the temperature exceeds 95 degrees Fahrenheit is not predictable

The key concept in the conclusion is reliable measure given the temperature doesnÂ´t exceed 95 F. Which is the only answer choice that addresses it? A. E is the 2nd best, although it is out of scope bc it deals w/ an scenario not contemplated in the conclusion (T > 95 F).

Kudos [?]: 27 [0], given: 0

Senior Manager
Joined: 24 Nov 2006
Posts: 349

Kudos [?]: 27 [0], given: 0

Re: The popular notion that a tree's age can be determined by [#permalink]

### Show Tags

07 Jan 2007, 09:35
Swagatalakshmi wrote:
The popular notion that a tree's age can be determined by counting the number of internal rings in its trunk is generally true. However, to help regulate the internal temperature of the tree, the outermost layers of wood of the Brazilian ash often peel away when the temperature exceeds 95 degrees Fahrenheit, leaving the tree with fewer rings than it would otherwise have. So if the temperature in the Brazilian ash's environment never exceeded 95 degrees Fahrenheit, its rings would be a reliable measure of the tree's age.

Which of the following is an assumption on which the argument above depends?
(A) The growth of new rings in a tree is not a function of levels of precipitation.
(B) Only the Brazilian ash loses rings because of excessive heat.
(C) Only one day of temperatures above 95 degrees Fahrenheit is needed to cause the Brazilian ash to lose a ring.
(D) The internal rings of all trees are of uniform thickness.
(E) The number of rings that will be lost when the temperature exceeds 95 degrees Fahrenheit is not predictable

The key concept in the conclusion is reliable measure given the temperature doesnÂ´t exceed 95 F. Which is the only answer choice that addresses it? A. E is the 2nd best, although it is out of scope bc it deals w/ an scenario not contemplated in the conclusion (T > 95 F).

Kudos [?]: 27 [0], given: 0

Manager
Joined: 16 Feb 2007
Posts: 71

Kudos [?]: 4 [1], given: 0

Re: The popular notion that a tree's age can be determined by [#permalink]

### Show Tags

01 Sep 2007, 16:17
1
KUDOS
ggarr wrote:
Swagatalakshmi,

Can we have the OR (official reasoning)?

for all who are interested: here is OR for OA:

(E) CORRECT. The conclusion is that the rings will be a reliable measure only if the temperature never exceeds 95 degrees. This is true only if there is no way to predict how many rings would be lost when the temperature does exceed 95 degrees. (If it were possible to predict this, one might be able to assess the age of a tree using its rings even if the temperature had exceeded 95 degrees.)

however i also think this question is strange... i also can live with answer choice C since the author says "never exceeds 95 degrees", i.e. there is an assumption that an exceeding at one day is enough...

Kudos [?]: 4 [1], given: 0

Re: The popular notion that a tree's age can be determined by   [#permalink] 01 Sep 2007, 16:17

Go to page    1   2    Next  [ 32 posts ]

Display posts from previous: Sort by