GMAT Question of the Day - Daily to your Mailbox; hard ones only

 It is currently 15 Feb 2019, 17:59

### 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
Your Progress

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 February
PrevNext
SuMoTuWeThFrSa
272829303112
3456789
10111213141516
17181920212223
242526272812
Open Detailed Calendar
• ### Free GMAT practice

February 15, 2019

February 15, 2019

10:00 PM EST

11:00 PM PST

Instead of wasting 3 months solving 5,000+ random GMAT questions, focus on just the 1,500 you need.

# If a and b are two-digit positive numbers and c is a three digit posit

 new topic post reply Question banks Downloads My Bookmarks Reviews Important topics
Author Message
TAGS:

### Hide Tags

Manager
Joined: 01 Jan 2016
Posts: 53
GPA: 3.75
WE: Engineering (Energy and Utilities)
If a and b are two-digit positive numbers and c is a three digit posit  [#permalink]

### Show Tags

Updated on: 07 Feb 2018, 10:39
5
00:00

Difficulty:

75% (hard)

Question Stats:

51% (02:15) correct 49% (02:32) wrong based on 64 sessions

### HideShow timer Statistics

If a and b are two-digit positive numbers and c is a three digit positive number, such that c=a+b. Is the unit digit of c the same as the unit digit of a?

1) All the digits of c are the same and all the digits of a are the same

2) The tens digit of a is the same as the tens digit of b

_________________

If you like it, give kudos. Thanks

The price of success is hard work, dedication to the job at hand, and the determination that whether we win or lose, we have applied the best of ourselves to the task at hand.
~Vince Lombardi

Originally posted by Teerex on 07 Feb 2018, 08:15.
Last edited by Teerex on 07 Feb 2018, 10:39, edited 1 time in total.
Senior PS Moderator
Joined: 26 Feb 2016
Posts: 3339
Location: India
GPA: 3.12
Re: If a and b are two-digit positive numbers and c is a three digit posit  [#permalink]

### Show Tags

07 Feb 2018, 09:48
1
Teerex wrote:
If a and b are two-digit positive numbers and c is a three digit positive number, such that c=a+b, is the unit digit of the same as the unit digit of a?

1) All the digits of C are the same and all the digits of a are the same

2) The tens digit of a is the same as the tens digit of b

Hi Teerex,

I suppose the question stem is incomplete in the highlighted part above
_________________

You've got what it takes, but it will take everything you've got

Manager
Joined: 01 Jan 2016
Posts: 53
GPA: 3.75
WE: Engineering (Energy and Utilities)
Re: If a and b are two-digit positive numbers and c is a three digit posit  [#permalink]

### Show Tags

07 Feb 2018, 10:40
pushpitkc wrote:
Teerex wrote:
If a and b are two-digit positive numbers and c is a three digit positive number, such that c=a+b, is the unit digit of the same as the unit digit of a?

1) All the digits of C are the same and all the digits of a are the same

2) The tens digit of a is the same as the tens digit of b

Hi Teerex,

I suppose the question stem is incomplete in the highlighted part above

Oops, my bad! Question has been modified. Thanks. +1
_________________

If you like it, give kudos. Thanks

The price of success is hard work, dedication to the job at hand, and the determination that whether we win or lose, we have applied the best of ourselves to the task at hand.
~Vince Lombardi

Retired Moderator
Joined: 25 Feb 2013
Posts: 1216
Location: India
GPA: 3.82
If a and b are two-digit positive numbers and c is a three digit posit  [#permalink]

### Show Tags

07 Feb 2018, 10:59
1
1
Teerex wrote:
If a and b are two-digit positive numbers and c is a three digit positive number, such that c=a+b. Is the unit digit of c the same as the unit digit of a?

1) All the digits of c are the same and all the digits of a are the same

2) The tens digit of a is the same as the tens digit of b

As $$c$$ is sum of two-digit numbers so the hundred's digit of $$c$$ will be $$1$$ (max possible value $$99+99=198$$)

Statement 1: implies $$c=111$$. $$a$$ cannot be $$11$$ because in this case no value of $$b$$ will add up to $$111$$

so for unit's digit of $$c$$ to be $$1$$, unit digit pairs of $$a$$ & $$b$$ can be (2,9),(3,8),(4,7),(5,6) etc.

Hence unit's digit of $$a$$ is not equal to unit's digit of $$c$$. Sufficient

Statement 2: nothing mentioned about $$c$$. Insufficient

Option A
Director
Joined: 31 Jul 2017
Posts: 518
Location: Malaysia
Schools: INSEAD Jan '19
GMAT 1: 700 Q50 V33
GPA: 3.95
WE: Consulting (Energy and Utilities)
If a and b are two-digit positive numbers and c is a three digit posit  [#permalink]

### Show Tags

13 Feb 2018, 03:03
Teerex wrote:
If a and b are two-digit positive numbers and c is a three digit positive number, such that c=a+b. Is the unit digit of c the same as the unit digit of a?

1) All the digits of c are the same and all the digits of a are the same

2) The tens digit of a is the same as the tens digit of b

Let $$a = mn, b = pq, c = rst.$$

Statement I:

$$111t = 11n + 10p + q$$.
Suppose, t = n
we get - $$100t = 10p+ q$$ ------------- This case is not possible as p,q are single digit.
Hence, t is not equal to n.

Statement II:

We get, $$100r + 10s + t = 20m + q + n.$$
Nothing can be decided on this. Insufficient.
_________________

If my Post helps you in Gaining Knowledge, Help me with KUDOS.. !!

If a and b are two-digit positive numbers and c is a three digit posit   [#permalink] 13 Feb 2018, 03:03
Display posts from previous: Sort by

# If a and b are two-digit positive numbers and c is a three digit posit

 new topic post reply Question banks Downloads My Bookmarks Reviews Important topics

 Powered by phpBB © phpBB Group | Emoji artwork provided by EmojiOne Kindly note that the GMAT® test is a registered trademark of the Graduate Management Admission Council®, and this site has neither been reviewed nor endorsed by GMAC®.