Author 
Message 
TAGS:

Hide Tags

Math Expert
Joined: 02 Sep 2009
Posts: 44599

A mother, who is 37 years old, and her son, who is 9 years old, have [#permalink]
Show Tags
21 Mar 2018, 23:12
Question Stats:
91% (00:31) correct 9% (00:58) wrong based on 44 sessions
HideShow timer Statistics



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 Checking answers 37 + 19 = 2* (9 + 19) 56 = 2 * 28 C



examPAL Representative
Joined: 07 Dec 2017
Posts: 292

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 (C) is our answer.
_________________
David Senior tutor at examPAL Signup for a free GMAT course
We won some awards:
Join our next webinar (free) Save up to $250 on examPAL packages (special for GMAT Club members)



SC Moderator
Joined: 22 May 2016
Posts: 1547

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
This post received KUDOS
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 Add the years to each person's age. Correct answer has 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 Answer C
_________________
At the still point, there the dance is.  T.S. Eliot Formerly genxer123



SVP
Joined: 26 Mar 2013
Posts: 1612

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 Answer: C



Target Test Prep Representative
Status: Head GMAT Instructor
Affiliations: Target Test Prep
Joined: 04 Mar 2011
Posts: 2273

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 Answer: C
_________________
Jeffery Miller
Head of GMAT Instruction
GMAT Quant SelfStudy Course
500+ lessons 3000+ practice problems 800+ HD solutions



eGMAT Representative
Joined: 04 Jan 2015
Posts: 1001

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 = \(379 = 28\) 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:
Simplifying the equation, we have: \(37 +x = 18 + 2x\) Or, \(x = 19\) years Answer: Option C
_________________
 '4 out of Top 5' Instructors on gmatclub  70 point improvement guarantee  www.egmat.com




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






