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# The exact cost price to make each unit of a widget is $7.6xy7, where x SORT BY: Tags: Show Tags Hide Tags Math Expert Joined: 02 Sep 2009 Posts: 94302 Own Kudos [?]: 640177 [40] Given Kudos: 84576 Most Helpful Reply Math Expert Joined: 02 Sep 2009 Posts: 94302 Own Kudos [?]: 640177 [9] Given Kudos: 84576 Manager Joined: 14 Oct 2012 Posts: 116 Own Kudos [?]: 260 [6] Given Kudos: 1023 General Discussion Manager Joined: 18 Dec 2014 Posts: 95 Own Kudos [?]: 49 [4] Given Kudos: 5 Re: The exact cost price to make each unit of a widget is$7.6xy7, where x [#permalink]
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The exact cost price to make each unit of a widget is $7.6xy7, where x and y represent single digits. What is the value of y? (1) When the cost is rounded to the nearest cent, it becomes$7.65.
(2) When the cost is rounded to the nearest tenth of a cent, it becomes $7.65. 1) Tells us that 7.6xy7 becomes 7.65 when rounded to the nearest cent, x = 4 or 5. This can happen by y being 1,2,3,4 and x being 5, or by y being 5,6,7,8,9 and x being 4. Not sufficient. 2) Tells us that 7.6xy7 becomes 7.650, this can happen by x being 4 and y being 9 (since the 7 rounds the 10th of a cent to 0, this must be 49). B? Intern Joined: 06 Apr 2015 Posts: 24 Own Kudos [?]: 2 [0] Given Kudos: 35 Re: The exact cost price to make each unit of a widget is$7.6xy7, where x [#permalink]
Bunuel wrote:
Bunuel wrote:
The exact cost price to make each unit of a widget is $7.6xy7, where x and y represent single digits. What is the value of y? (1) When the cost is rounded to the nearest cent, it becomes$7.65.
(2) When the cost is rounded to the nearest tenth of a cent, it becomes $7.65. Kudos for a correct solution. VERITAS PREP OFFICIAL SOLUTION: The question is based on rounding. We need to figure out the value of y given some rounding scenarios. Let’s look at them one by one. Statement 1: When the cost is rounded to the nearest cent, it becomes$7.65.

When rounded to the nearest cent, the cost becomes 7 dollars and 65 cents. 6xy7 cents got rounded to 65 cents. When will .6xy7 get rounded to .65? When .6xy7 lies anywhere in the range .6457 to .6547. Note that in all these cases, when you round the number to 2 digits, it will become .65.

Say price is 7.6468. We need to drop 68 but since 6 is ‘5 or greater’, 4 gets rounded up to 5.

Similarly, say the price is 7.6543. We need to drop 43. Since 4 is ‘4 or smaller’, 5 stays as it is.

So x and y can take various different values. This statement alone is not sufficient.

Statement 2: When the cost is rounded to the nearest tenth of a cent, it becomes $7.65 Now the cost is rounded to the tenth of a cent which means 3 places after the decimal. But the cost is given to us as$7.65. Since we need 3 places, the cost must be $7.650 (which will be written as$7.65)

When will 7.6xy7 get rounded to 7.650? Now this is the tricky part of the question – from 7.6xy7, you need to drop the 7 and round up y. When you do that, you get 7.650. This means 7.6xy7 must have been 7.6497. Only in this case, when we drop the 7, we round up the 9 to make 10, carry the 1 over to 4 and make it 5. This is the only way to get 7.650 on rounding 7.6xy7 to the tenth of a cent. Hence x must be 4 and y must be 9. This statement alone is sufficient to answer the question.

For statement 2 can't we get the same result if x and y were 4 and 8? i.e. 7.6487?
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Re: The exact cost price to make each unit of a widget is $7.6xy7, where x [#permalink] kelvind13 wrote: For statement 2 can't we get the same result if x and y were 4 and 8? i.e. 7.6487? Then we receive 7.649 because we need to round up to tenth of cent Intern Joined: 30 Oct 2010 Posts: 43 Own Kudos [?]: 91 [0] Given Kudos: 23 Re: The exact cost price to make each unit of a widget is$7.6xy7, where x [#permalink]
Harley1980 wrote:
kelvind13 wrote:
For statement 2 can't we get the same result if x and y were 4 and 8? i.e. 7.6487?

Then we receive 7.649 because we need to round up to tenth of cent

Hi,

Can someone explain the rounding up to the tenth of a cent concept with some examples?

regards,
karthik
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Re: The exact cost price to make each unit of a widget is $7.6xy7, where x [#permalink] 2 Bookmarks iikarthik wrote: Harley1980 wrote: kelvind13 wrote: For statement 2 can't we get the same result if x and y were 4 and 8? i.e. 7.6487? Then we receive 7.649 because we need to round up to tenth of cent Hi, Can someone explain the rounding up to the tenth of a cent concept with some examples? regards, karthik Rounding up of 0.123 to the nearest tenth will be 0.1 Rounding up of 0.125 to the nearest tenth will be 0.1 Rounding up of 0.153 to the nearest tenth will be 0.2 Rounding up of 0.156 to the nearest tenth will be 0.2 Rounding up of 7.156 to the nearest tenth will be 7.2 For rounding to -ths (tenths or hundredths or thousandths etc) look at the digit to the right of the digit in question. If this "to the right" digit is <5, keep the same "digit in question". But if this "to the right" digit is $$\geq$$ 5, then "digit in question" gets incremented by 1. Read: https://www.gmatclub.com/forum/veritas-prep-resource-links-no-longer-available-399979.html#/2014/06 ... or-a-five/ Hope this helps. Manager Joined: 29 Sep 2016 Posts: 85 Own Kudos [?]: 21 [0] Given Kudos: 40 Re: The exact cost price to make each unit of a widget is$7.6xy7, where x [#permalink]
Bunuel wrote:
Bunuel wrote:
The exact cost price to make each unit of a widget is $7.6xy7, where x and y represent single digits. What is the value of y? (1) When the cost is rounded to the nearest cent, it becomes$7.65.
(2) When the cost is rounded to the nearest tenth of a cent, it becomes $7.65. Kudos for a correct solution. VERITAS PREP OFFICIAL SOLUTION: The question is based on rounding. We need to figure out the value of y given some rounding scenarios. Let’s look at them one by one. Statement 1: When the cost is rounded to the nearest cent, it becomes$7.65.

When rounded to the nearest cent, the cost becomes 7 dollars and 65 cents. 6xy7 cents got rounded to 65 cents. When will .6xy7 get rounded to .65? When .6xy7 lies anywhere in the range .6457 to .6547. Note that in all these cases, when you round the number to 2 digits, it will become .65.

Say price is 7.6468. We need to drop 68 but since 6 is ‘5 or greater’, 4 gets rounded up to 5.

Similarly, say the price is 7.6543. We need to drop 43. Since 4 is ‘4 or smaller’, 5 stays as it is.

So x and y can take various different values. This statement alone is not sufficient.

Statement 2: When the cost is rounded to the nearest tenth of a cent, it becomes $7.65 Now the cost is rounded to the tenth of a cent which means 3 places after the decimal. But the cost is given to us as$7.65. Since we need 3 places, the cost must be $7.650 (which will be written as$7.65)

When will 7.6xy7 get rounded to 7.650? Now this is the tricky part of the question – from 7.6xy7, you need to drop the 7 and round up y. When you do that, you get 7.650. This means 7.6xy7 must have been 7.6497. Only in this case, when we drop the 7, we round up the 9 to make 10, carry the 1 over to 4 and make it 5. This is the only way to get 7.650 on rounding 7.6xy7 to the tenth of a cent. Hence x must be 4 and y must be 9. This statement alone is sufficient to answer the question.

Hi Bunuel
Need a clarification as I am not very thorough with rounding off concept.
What if y=0 & x =5, 7.6507. Wouldn't this no. also be rounded to 7.65 ?
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Re: The exact cost price to make each unit of a widget is $7.6xy7, where x [#permalink] Expert Reply AKY13 wrote: Bunuel wrote: Bunuel wrote: The exact cost price to make each unit of a widget is$7.6xy7, where x and y represent single digits. What is the value of y?

(1) When the cost is rounded to the nearest cent, it becomes $7.65. (2) When the cost is rounded to the nearest tenth of a cent, it becomes$7.65.

Kudos for a correct solution.

VERITAS PREP OFFICIAL SOLUTION:

The question is based on rounding. We need to figure out the value of y given some rounding scenarios. Let’s look at them one by one.

Statement 1: When the cost is rounded to the nearest cent, it becomes $7.65. When rounded to the nearest cent, the cost becomes 7 dollars and 65 cents. 6xy7 cents got rounded to 65 cents. When will .6xy7 get rounded to .65? When .6xy7 lies anywhere in the range .6457 to .6547. Note that in all these cases, when you round the number to 2 digits, it will become .65. Say price is 7.6468. We need to drop 68 but since 6 is ‘5 or greater’, 4 gets rounded up to 5. Similarly, say the price is 7.6543. We need to drop 43. Since 4 is ‘4 or smaller’, 5 stays as it is. So x and y can take various different values. This statement alone is not sufficient. Statement 2: When the cost is rounded to the nearest tenth of a cent, it becomes$7.65

Now the cost is rounded to the tenth of a cent which means 3 places after the decimal. But the cost is given to us as $7.65. Since we need 3 places, the cost must be$7.650 (which will be written as $7.65) When will 7.6xy7 get rounded to 7.650? Now this is the tricky part of the question – from 7.6xy7, you need to drop the 7 and round up y. When you do that, you get 7.650. This means 7.6xy7 must have been 7.6497. Only in this case, when we drop the 7, we round up the 9 to make 10, carry the 1 over to 4 and make it 5. This is the only way to get 7.650 on rounding 7.6xy7 to the tenth of a cent. Hence x must be 4 and y must be 9. This statement alone is sufficient to answer the question. Answer (B) Hi Bunuel Need a clarification as I am not very thorough with rounding off concept. What if y=0 & x =5, 7.6507. Wouldn't this no. also be rounded to 7.65 ? 7.6507 rounded to the nearest tenth of a cent is 7.651. Manager Joined: 11 Aug 2019 Posts: 68 Own Kudos [?]: 23 [0] Given Kudos: 112 Re: The exact cost price to make each unit of a widget is$7.6xy7, where x [#permalink]
Bunuel wrote:
Bunuel wrote:
The exact cost price to make each unit of a widget is $7.6xy7, where x and y represent single digits. What is the value of y? (1) When the cost is rounded to the nearest cent, it becomes$7.65.
(2) When the cost is rounded to the nearest tenth of a cent, it becomes $7.65. Kudos for a correct solution. VERITAS PREP OFFICIAL SOLUTION: The question is based on rounding. We need to figure out the value of y given some rounding scenarios. Let’s look at them one by one. Statement 1: When the cost is rounded to the nearest cent, it becomes$7.65.

When rounded to the nearest cent, the cost becomes 7 dollars and 65 cents. 6xy7 cents got rounded to 65 cents. When will .6xy7 get rounded to .65? When .6xy7 lies anywhere in the range .6457 to .6547. Note that in all these cases, when you round the number to 2 digits, it will become .65.

Say price is 7.6468. We need to drop 68 but since 6 is ‘5 or greater’, 4 gets rounded up to 5.

Similarly, say the price is 7.6543. We need to drop 43. Since 4 is ‘4 or smaller’, 5 stays as it is.

So x and y can take various different values. This statement alone is not sufficient.

Statement 2: When the cost is rounded to the nearest tenth of a cent, it becomes $7.65 Now the cost is rounded to the tenth of a cent which means 3 places after the decimal. But the cost is given to us as$7.65. Since we need 3 places, the cost must be $7.650 (which will be written as$7.65)

When will 7.6xy7 get rounded to 7.650? Now this is the tricky part of the question – from 7.6xy7, you need to drop the 7 and round up y. When you do that, you get 7.650. This means 7.6xy7 must have been 7.6497. Only in this case, when we drop the 7, we round up the 9 to make 10, carry the 1 over to 4 and make it 5. This is the only way to get 7.650 on rounding 7.6xy7 to the tenth of a cent. Hence x must be 4 and y must be 9. This statement alone is sufficient to answer the question.

Hi Bunuel,

For Statement 1, what about 7.6547, will it belong to that group? If we look only until 4, then it'd become 7.65, but if we include 7, it'll become 7.655, which will become 7.66. So when x equals 5, shouldn't y only go to 3, not 4? Thanks!
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Re: The exact cost price to make each unit of a widget is $7.6xy7, where x [#permalink] 1 Bookmarks Expert Reply shabuzen102 wrote: Bunuel wrote: Bunuel wrote: The exact cost price to make each unit of a widget is$7.6xy7, where x and y represent single digits. What is the value of y?

(1) When the cost is rounded to the nearest cent, it becomes $7.65. (2) When the cost is rounded to the nearest tenth of a cent, it becomes$7.65.

Kudos for a correct solution.

VERITAS PREP OFFICIAL SOLUTION:

The question is based on rounding. We need to figure out the value of y given some rounding scenarios. Let’s look at them one by one.

Statement 1: When the cost is rounded to the nearest cent, it becomes $7.65. When rounded to the nearest cent, the cost becomes 7 dollars and 65 cents. 6xy7 cents got rounded to 65 cents. When will .6xy7 get rounded to .65? When .6xy7 lies anywhere in the range .6457 to .6547. Note that in all these cases, when you round the number to 2 digits, it will become .65. Say price is 7.6468. We need to drop 68 but since 6 is ‘5 or greater’, 4 gets rounded up to 5. Similarly, say the price is 7.6543. We need to drop 43. Since 4 is ‘4 or smaller’, 5 stays as it is. So x and y can take various different values. This statement alone is not sufficient. Statement 2: When the cost is rounded to the nearest tenth of a cent, it becomes$7.65

Now the cost is rounded to the tenth of a cent which means 3 places after the decimal. But the cost is given to us as $7.65. Since we need 3 places, the cost must be$7.650 (which will be written as $7.65) When will 7.6xy7 get rounded to 7.650? Now this is the tricky part of the question – from 7.6xy7, you need to drop the 7 and round up y. When you do that, you get 7.650. This means 7.6xy7 must have been 7.6497. Only in this case, when we drop the 7, we round up the 9 to make 10, carry the 1 over to 4 and make it 5. This is the only way to get 7.650 on rounding 7.6xy7 to the tenth of a cent. Hence x must be 4 and y must be 9. This statement alone is sufficient to answer the question. Answer (B) Hi Bunuel, For Statement 1, what about 7.6547, will it belong to that group? If we look only until 4, then it'd become 7.65, but if we include 7, it'll become 7.655, which will become 7.66. So when x equals 5, shouldn't y only go to 3, not 4? Thanks! That;s not true. Rounding is simplifying a number to a certain place value. To round the decimal drop the extra decimal places, and if the first dropped digit is 5 or greater, round up the last digit that you keep. If the first dropped digit is 4 or smaller, round down (keep the same) the last digit that you keep. Example: 5.3485 rounded to the nearest tenth = 5.3, since the dropped 4 is less than 5. 5.3485 rounded to the nearest hundredth = 5.35, since the dropped 8 is greater than 5. 5.3485 rounded to the nearest thousandth = 5.349, since the dropped 5 is equal to 5. Hope it helps. Director Joined: 21 Feb 2017 Posts: 509 Own Kudos [?]: 1074 [1] Given Kudos: 1091 Location: India GMAT 1: 700 Q47 V39 Re: The exact cost price to make each unit of a widget is$7.6xy7, where x [#permalink]
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Hi Bunuel!
When statement 2 says round it to the nearest tenth of a cent is that different from round to the nearest tenth? If yes, how so? what does rounding to nearest tenth/hundredth of a cent mean?
Because if not, then don't both statements tell us the same info :S

Thanks
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Re: The exact cost price to make each unit of a widget is $7.6xy7, where x [#permalink] Bunuel wrote: The exact cost price to make each unit of a widget is$7.6xy7, where x and y represent single digits. What is the value of y?

(1) When the cost is rounded to the nearest cent, it becomes $7.65. (2) When the cost is rounded to the nearest tenth of a cent, it becomes$7.65.

Kudos for a correct solution.

Rounding to the nearest tenth of a cent means we need to round up to 3 decimal places.
Can someone please confirm?
Thanks
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Re: The exact cost price to make each unit of a widget is $7.6xy7, where x [#permalink] chetan2u, Bunuel, VeritasKarishma, GMATBusters, nick1816 -- why does rounding one tenth of a cent, mean 3 decimal places ? i thought it meant the tenth digit in a number 34.869 -- i thought the tenth digit of a cent was right after the decimal (=8) Please explain logically why tenth of a cent means 9. Thank you ! RC & DI Moderator Joined: 02 Aug 2009 Status:Math and DI Expert Posts: 11468 Own Kudos [?]: 34261 [5] Given Kudos: 322 Re: The exact cost price to make each unit of a widget is$7.6xy7, where x [#permalink]
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jabhatta@umail.iu.edu wrote:
chetan2u, Bunuel, VeritasKarishma, GMATBusters, nick1816 -- why does rounding one tenth of a cent, mean 3 decimal places ?

i thought it meant the tenth digit in a number

34.869 -- i thought the tenth digit of a cent was right after the decimal (=8)

Please explain logically why tenth of a cent means 9.

Thank you !

Hi

The amount is in dollars, whereas we are talking about tenth of cents.
If the amount is $7.1234, then in cents is 712.34 cents and the tenth of cents here is 3 now. Target Test Prep Representative Joined: 04 Mar 2011 Status:Head GMAT Instructor Affiliations: Target Test Prep Posts: 3037 Own Kudos [?]: 6556 [0] Given Kudos: 1646 Re: The exact cost price to make each unit of a widget is$7.6xy7, where x [#permalink]
Bunuel wrote:
The exact cost price to make each unit of a widget is $7.6xy7, where x and y represent single digits. What is the value of y? (1) When the cost is rounded to the nearest cent, it becomes$7.65.
(2) When the cost is rounded to the nearest tenth of a cent, it becomes $7.65. The cost is$7.6xy7, and x and y are single digits.

We need to answer the question:

y = ?

Statement One Alone:

=> When the cost is rounded to the nearest cent, it becomes $7.65. If$7.6xy7 = $7.6497, then after being rounded to the nearest cent, it becomes$7.65. In this case, y = 9.

Whereas, if $7.6xy7 =$7.6507, then after being rounded to the nearest cent, it becomes $7.65 again. In this case, y = 0. Statement one is not sufficient. Eliminate answer choices A and D. Statement Two Alone: => When the cost is rounded to the nearest tenth of a cent, it becomes$7.65.

In this case, the rounded value actually is $7.650, which, of course, simplifies to$7.65.

The place of a tenth of a cent is the third digit right to the decimal point, so the fourth digit right to the decimal point has to be considered during the rounding process. Since that fourth digit is 7, which is greater than or equal to 5, we have to round up the third digit. So, before being rounded, y must have been 9.

(Note: We don’t have to worry about the value of x because the question is about the value of y.)

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