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

 It is currently 17 Jul 2018, 16:24

### 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

# A mother, who is 37 years old, and her son, who is 9 years old, have

Author Message
TAGS:

### Hide Tags

Math Expert
Joined: 02 Sep 2009
Posts: 47037
A mother, who is 37 years old, and her son, who is 9 years old, have [#permalink]

### Show Tags

21 Mar 2018, 23:12
00:00

Difficulty:

25% (medium)

Question Stats:

91% (00:34) correct 9% (00:58) wrong based on 46 sessions

### HideShow timer Statistics

A mother, who is 37 years old, and her son, who is 9 years old, have the same birthday anniversary month and day. In how many years from now will the mother be twice as old as her son?

(A) 11
(B) 15
(C) 19
(D) 23
(E) 28

_________________
Intern
Joined: 14 Mar 2018
Posts: 10
Re: A mother, who is 37 years old, and her son, who is 9 years old, have [#permalink]

### Show Tags

21 Mar 2018, 23:25
Bunuel wrote:
A mother, who is 37 years old, and her son, who is 9 years old, have the same birthday anniversary month and day. In how many years from now will the mother be twice as old as her son?

(A) 11
(B) 15
(C) 19
(D) 23
(E) 28

37 + 19 = 2* (9 + 19)
56 = 2 * 28
C
examPAL Representative
Joined: 07 Dec 2017
Posts: 501
Re: A mother, who is 37 years old, and her son, who is 9 years old, have [#permalink]

### Show Tags

22 Mar 2018, 01:05
Bunuel wrote:
A mother, who is 37 years old, and her son, who is 9 years old, have the same birthday anniversary month and day. In how many years from now will the mother be twice as old as her son?

(A) 11
(B) 15
(C) 19
(D) 23
(E) 28

As it is easy to translate the question into an equation, we'll do so.
This is a Precise approach.

In x years, the mother will be 37 + x years old and the son 9 + x years old.
So, we need to solve 37+x = 2(9+x) --> 37+x = 18+2x --> 19 = x

_________________

David
Senior tutor at examPAL
Signup for a free GMAT course

We won some awards:

Save up to \$250 on examPAL packages (special for GMAT Club members)

SC Moderator
Joined: 22 May 2016
Posts: 1827
A mother, who is 37 years old, and her son, who is 9 years old, have [#permalink]

### Show Tags

22 Mar 2018, 17:58
1
Bunuel wrote:
A mother, who is 37 years old, and her son, who is 9 years old, have the same birthday anniversary month and day. In how many years from now will the mother be twice as old as her son?

(A) 11
(B) 15
(C) 19
(D) 23
(E) 28

Answer choices are fast, especially if the equation is elusive.

Mom is 37
Son is 9
Mom's age = 2 * son's age

(A) 11
Mom: 37 + 11 = 46
Son: 9 + 11 = 20
46 is not (2 * 20) - NO

(B) 15
Mom: 37 + 15 = 52
Son: 9 + 15 = 24
52 is not (2 * 24) - NO

(C) 19
Mom: 37 + 19 = 56
Son: 9 + 19 = 28
CORRECT: 56 = (2 * 28) YES

This question does not have VIC. There is only one right answer. That's C. In case you were to start with E . .

(D) 23
Mom: 37 + 23 = 60
Son: 9 + 23 = 32
60 is not (2 * 32) - NO

(E) 28
Mom: 37 + 28 = 65
Son: 9 + 28 = 37
65 is not (2 * 37) - NO

_________________

In the depths of winter, I finally learned
that within me there lay an invincible summer.

SVP
Joined: 26 Mar 2013
Posts: 1719
Re: A mother, who is 37 years old, and her son, who is 9 years old, have [#permalink]

### Show Tags

23 Mar 2018, 10:24
Bunuel wrote:
A mother, who is 37 years old, and her son, who is 9 years old, have the same birthday anniversary month and day. In how many years from now will the mother be twice as old as her son?

(A) 11
(B) 15
(C) 19
(D) 23
(E) 28

Let future years = x

37 + x = 2 (9 + x)

37 + x = 18 +2x

x =19

Target Test Prep Representative
Affiliations: Target Test Prep
Joined: 04 Mar 2011
Posts: 2669
Re: A mother, who is 37 years old, and her son, who is 9 years old, have [#permalink]

### Show Tags

23 Mar 2018, 12:43
Bunuel wrote:
A mother, who is 37 years old, and her son, who is 9 years old, have the same birthday anniversary month and day. In how many years from now will the mother be twice as old as her son?

(A) 11
(B) 15
(C) 19
(D) 23
(E) 28

Let x = the number of years from now the mother will be twice as old as her son. At that time in the future, she will be (37 + x) years old, and her son will be (x + 9) years old. Also, she will then be twice his age. We can create the following equation:

37 + x = 2(x + 9)

37 + x = 2x + 18

19 = x

_________________

Jeffery Miller

GMAT Quant Self-Study Course
500+ lessons 3000+ practice problems 800+ HD solutions

e-GMAT Representative
Joined: 04 Jan 2015
Posts: 1755
Re: A mother, who is 37 years old, and her son, who is 9 years old, have [#permalink]

### Show Tags

26 Mar 2018, 09:22

Solution:

Given:
• Age of mother = $$37$$ years

• Age of Son = $$9$$ years

• Both have same birthday month and day

o Inference: Difference in ages = $$37-9 = 28$$ years

Working out:

• We need the age of the mother to be twice that of his son.

• Let us assume that after x years, the mother will be twice the age as her son.

o If we translate this statement into a mathematical equation, we get:

 $$37+x = 2* (9+x)$$

Simplifying the equation, we have:

$$37 +x = 18 + 2x$$

Or, $$x = 19$$ years

_________________

Ace GMAT quant
Articles and Question to reach Q51 | Question of the week

Number Properties – Even Odd | LCM GCD
Word Problems – Percentage 1 | Percentage 2 | Time and Work 1 | Time and Work 2 | Time, Speed and Distance 1 | Time, Speed and Distance 2
Advanced Topics- Permutation and Combination 1 | Permutation and Combination 2 | Permutation and Combination 3 | Probability
Geometry- Triangles 1 | Triangles 2 | Triangles 3 | Common Mistakes in Geometry
Algebra- Wavy line

Practice Questions
Number Properties 1 | Number Properties 2 | Algebra 1 | Geometry | Prime Numbers | Absolute value equations | Sets

| '4 out of Top 5' Instructors on gmatclub | 70 point improvement guarantee | www.e-gmat.com

Re: A mother, who is 37 years old, and her son, who is 9 years old, have   [#permalink] 26 Mar 2018, 09:22
Display posts from previous: Sort by

# Events & Promotions

 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®.