Last visit was: 15 Dec 2024, 13:03 It is currently 15 Dec 2024, 13:03
Close
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
Not interested in getting valuable practice questions and articles delivered to your email? No problem, unsubscribe here.
Close
Request Expert Reply
Confirm Cancel
User avatar
Bunuel
User avatar
Math Expert
Joined: 02 Sep 2009
Last visit: 15 Dec 2024
Posts: 97,886
Own Kudos:
686,156
 []
Given Kudos: 88,273
Products:
Expert reply
Active GMAT Club Expert! Tag them with @ followed by their username for a faster response.
Posts: 97,886
Kudos: 686,156
 []
Kudos
Add Kudos
1
Bookmarks
Bookmark this Post
avatar
kablayi
Joined: 05 Mar 2015
Last visit: 08 Feb 2023
Posts: 26
Own Kudos:
19
 []
Given Kudos: 111
Location: Azerbaijan
GMAT 1: 530 Q42 V21
GMAT 2: 600 Q42 V31
GMAT 3: 700 Q47 V38
GMAT 3: 700 Q47 V38
Posts: 26
Kudos: 19
 []
1
Kudos
Add Kudos
Bookmarks
Bookmark this Post
User avatar
generis
User avatar
Senior SC Moderator
Joined: 22 May 2016
Last visit: 18 Jun 2022
Posts: 5,316
Own Kudos:
36,322
 []
Given Kudos: 9,464
Products:
Expert reply
Posts: 5,316
Kudos: 36,322
 []
2
Kudos
Add Kudos
Bookmarks
Bookmark this Post
User avatar
dave13
Joined: 09 Mar 2016
Last visit: 23 Nov 2024
Posts: 1,133
Own Kudos:
Given Kudos: 3,851
Posts: 1,133
Kudos: 1,057
Kudos
Add Kudos
Bookmarks
Bookmark this Post
generis
Bunuel
Two years ago, Cecilia's mother was three times as old as Cecilia. In 12 years, Cecilia's mother will be twice as old as Cecilia. How old is Cecilia currently?

A. 10
B. 12
C. 14
D. 16
E. 18
C = Cecilia
M = Mother

Two years ago:
C's mother was three times as old as C
M - 2 = 3(C - 2)
M - 2 = 3C - 6
M = 3C - 4 ---> Use this for next equation

In 12 years:
C's mother will be twice as old as C
M + 12 = 2(C + 12) - substitute
(3C - 4) + 12 = 2C + 24
C = 16

Answer D


Hello generis, can you advice if my approach is correct :)

C = Cecilia
M = Mother

m=3c-2 <---- Two years ago, Cecilia's mother was three times as old as Cecilia
m=12+2c < ---- In 12 years, Cecilia's mother will be twice as old as Cecilia

How old is Cecilia currently? <--- C ? :)

3c-2 = 12+2c
3c-2c = 12+2
c= 14

Since two years ago, Cecilia's mother was three times as old as Cecilia - 2, so we add those two years to 14 and get 16 :) no ? :? I think I missed something though I answered correctly :)
User avatar
generis
User avatar
Senior SC Moderator
Joined: 22 May 2016
Last visit: 18 Jun 2022
Posts: 5,316
Own Kudos:
36,322
 []
Given Kudos: 9,464
Products:
Expert reply
Posts: 5,316
Kudos: 36,322
 []
1
Kudos
Add Kudos
Bookmarks
Bookmark this Post
dave13
Bunuel
Two years ago, Cecilia's mother was three times as old as Cecilia. In 12 years, Cecilia's mother will be twice as old as Cecilia. How old is Cecilia currently?

A. 10
B. 12
C. 14
D. 16
E. 18
Hello generis, can you advice if my approach is correct :)

C = Cecilia
M = Mother

m=3c-2 <---- Two years ago, Cecilia's mother was three times as old as Cecilia
m=12+2c < ---- In 12 years, Cecilia's mother will be twice as old as Cecilia

How old is Cecilia currently? <--- C ? :)

3c-2 = 12+2c
3c-2c = 12+2
c= 14

Since two years ago, Cecilia's mother was three times as old as Cecilia - 2, so we add those two years to 14 and get 16 :) no ? :? I think I missed something though I answered correctly :)
dave13 , you're not missing anything. You did one step in your head (adding 2 at the end). I think that's what you're sensing.

You and kablayi (welcome!) used similar approaches with variables defined a bit differently.

You just didn't "remind" yourself explicitly -- as kablayi did by writing Cecilia's age "now" as "x + 2" -- that whatever you calculated for Cecilia's age would require you to add 2.

In short, good instincts! :-)
avatar
dontgiveup2020
Joined: 28 Dec 2017
Last visit: 25 Jul 2018
Posts: 29
Own Kudos:
Posts: 29
Kudos: 7
Kudos
Add Kudos
Bookmarks
Bookmark this Post
M = Cecilia's mother
C = Cecilia

Two years ago:
(M - 2) = 3(C - 2)
Simplifying the equation, M - 3C = -4 Equation 1

In twelve years:
(M + 12) = 2(C + 12)
Simplifying the equation, M - 2C = 12 Equation 2

Subtracting Equation 1 from Equation 2,
M - 2C = 12
- M - 3C = -4
C = 16. Hence Cecilia is currently 16 years old (Option D)
User avatar
saraheja
Joined: 01 Jun 2015
Last visit: 08 Jul 2018
Posts: 36
Own Kudos:
30
 []
Given Kudos: 7
Location: India
Products:
Posts: 36
Kudos: 30
 []
1
Kudos
Add Kudos
Bookmarks
Bookmark this Post
Current age of Cecilia = y and current age of Cecilia's mother = y

According to given statements :

x-2 = 3y & x+12 = 2(y+12)

Solving y =10
User avatar
bumpbot
User avatar
Non-Human User
Joined: 09 Sep 2013
Last visit: 04 Jan 2021
Posts: 35,836
Own Kudos:
Posts: 35,836
Kudos: 930
Kudos
Add Kudos
Bookmarks
Bookmark this Post
Hello from the GMAT Club BumpBot!

Thanks to another GMAT Club member, I have just discovered this valuable topic, yet it had no discussion for over a year. I am now bumping it up - doing my job. I think you may find it valuable (esp those replies with Kudos).

Want to see all other topics I dig out? Follow me (click follow button on profile). You will receive a summary of all topics I bump in your profile area as well as via email.
Moderator:
Math Expert
97886 posts