Last visit was: 22 Apr 2026, 10:29 It is currently 22 Apr 2026, 10:29
Home
Messages
Tests
Schools
Events
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.
Go to My Error Log Learn more
Close
Request Expert Reply
Confirm Cancel
Back to Forum
Create Topic
User avatar
Bunuel
User avatar
Math Expert
Joined: 02 Sep 2009
Last visit: 22 Apr 2026
Posts: 109,747
Own Kudos:
810,636
 [20]
Given Kudos: 105,820
Products:
GMAT Club Tests Forum Quiz
Expert
Expert reply
Active GMAT Club Expert! Tag them with @ followed by their username for a faster response.
Posts: 109,747
Kudos: 810,636
 [20]
In three years, Janice will be three times as old as her daughter. Six 15 Aug 2016, 03:56
1
Kudos
Add Kudos
19
Bookmarks
Bookmark this Post
00:00
Start Timer
Pause Timer
Resume Timer
Show Answer
Hide
Show
History
D
Be sure to select an answer first to save it in the Error Log before revealing the correct answer (OA)!

Difficulty:

35% (medium)

Question Stats:

77% (02:47) correct 23% (02:58) wrong based on 289 sessions

History

Date
Time
Result
Not Attempted Yet
In three years, Janice will be three times as old as her daughter. Six years ago, her age was her daughter’s age squared. How old is Janice?

A. 18
B. 36
C. 40
D. 42
E. 45
ShowHide Answer
Official Answer
D
Most Helpful Reply
User avatar
BrentGMATPrepNow
User avatar
Major Poster
Joined: 12 Sep 2015
Last visit: 31 Oct 2025
Posts: 6,733
Own Kudos:
36,443
 [10]
Given Kudos: 799
Location: Canada
Expert
Expert reply
Posts: 6,733
Kudos: 36,443
 [10]
In three years, Janice will be three times as old as her daughter. Six 26 Aug 2017, 07:35
8
Kudos
Add Kudos
2
Bookmarks
Bookmark this Post
Bunuel
In three years, Janice will be three times as old as her daughter. Six years ago, her age was her daughter’s age squared. How old is Janice?

A. 18
B. 36
C. 40
D. 42
E. 45
Show more

One of my students (username: aashaybaindur) just pointed out a super fast way to solve this question:

GIVEN: SIX YEARS AGO, Janice's age was her daughter’s age squared.

Take each answer choice (Janice's PRESENT age) and subtract 6 years to see which one(s) yield(s) the square of an integer.
A. 18 - 6 = 12. Since 12 is NOT the square of an integer, ELIMINATE A
B. 36 - 6 = 30. Since 30 is NOT the square of an integer, ELIMINATE B
C. 40 - 6 = 34. Since 34 is NOT the square of an integer, ELIMINATE C
D. 42 - 6 = 36. Since 36 IS the square of an integer, KEEP D
E. 45 - 6 = 39. Since 39 is NOT the square of an integer, ELIMINATE E

Answer:
Show Spoiler
D

ASIDE: It doesn't take long to confirm that D is, indeed, the correct answer.

Cheers,
Brent
General Discussion
User avatar
msk0657
User avatar
Retired Moderator
Joined: 26 Nov 2012
Last visit: 14 Feb 2020
Posts: 455
Own Kudos:
569
 [1]
Given Kudos: 46
Posts: 455
Kudos: 569
 [1]
In three years, Janice will be three times as old as her daughter. Six 15 Aug 2016, 04:54
1
Kudos
Add Kudos
Bookmarks
Bookmark this Post
Bunuel
In three years, Janice will be three times as old as her daughter. Six years ago, her age was her daughter’s age squared. How old is Janice?

A. 18
B. 36
C. 40
D. 42
E. 45
Show more

Let Jane's age be J and daughters' age be D...

Given J + 3 = 3(D + 3 ) => J - 6 = 3D -> Eq1.

Given J-6 = (D-6)^2 --> Eq 2..

sub J-6 value in eq 2... 3D = D^2 - 12D + 36.
0 = D^2 - 15D + 36 => D = 12 or D = 3.

When D = 12 we get from eq 1... J+3 = 45 => J =42..
When D = 3 ..we get from eq 1.. J+3 = 18 => J = 15...

In the above options only 42 exits..

IMO option D is correct answer..
User avatar
BrentGMATPrepNow
User avatar
Major Poster
Joined: 12 Sep 2015
Last visit: 31 Oct 2025
Posts: 6,733
Own Kudos:
36,443
 [3]
Given Kudos: 799
Location: Canada
Expert
Expert reply
Posts: 6,733
Kudos: 36,443
 [3]
In three years, Janice will be three times as old as her daughter. Six Updated on: 03 Nov 2019, 12:09
Originally posted by BrentGMATPrepNow on 15 Aug 2016, 07:50.
Last edited by BrentGMATPrepNow on 03 Nov 2019, 12:09, edited 1 time in total.
3
Kudos
Add Kudos
Bookmarks
Bookmark this Post
Bunuel
In three years, Janice will be three times as old as her daughter. Six years ago, her age was her daughter’s age squared. How old is Janice?

A. 18
B. 36
C. 40
D. 42
E. 45
Show more

msk0657's solution is great.
Here's an approach that uses 1 variable:

Let J = Janice's PRESENT AGE
So, 6 years ago, Janice's age WAS J - 6
Also, in 3 years, Janice's age WILL BE J + 3


Six years ago, Janice's age was her daughter’s age squared.
6 years ago, Janice's age WAS J - 6
So, 6 years ago, the DAUGHTER'S age was √(J - 6)

If the DAUGHTER'S age was √(J - 6) 6 years ago, then to find her age 3 years from now, we must add 9 to her age 6 years ago.
In other words, √(J - 6) + 9 = the DAUGHTER'S age in 3 years

In three years, Janice will be three times as old as her daughter
√(J - 6) + 9 = the DAUGHTER'S age in 3 years
J + 3 = Janice's age in 3 years
At this point, Janice's age is 3 times her daughter's age. So, to make the two values EQUAL, we must multiply the smaller value (the daughter's age) by 3
We get: 3[√(J - 6) + 9] = J + 3 ......now solve for J
Divide both sides by 3 to get: √(J - 6) + 9 = (J/3) + 1
Subtract 9 from both sides to get: √(J - 6) = (J/3) - 8

IMPORTANT: At this point, you might find it easier to plug in the answer choices and see which one satisfies the above equation...
Notice that the correct value of J will yield an INTEGER value when plugged into √(J - 6) AND it will yield an INTEGER value when plugged into (J/3)
We can quickly see that only answer choice D (J = 42) will yield integer values for √(J - 6) AND (J/3)

Answer:
Show Spoiler
D
avatar
sssjav
avatar
Joined: 05 Dec 2017
Last visit: 17 Jul 2019
Posts: 16
Own Kudos:
38
 [2]
Given Kudos: 32
GMAT 1: 710 Q49 V38
GMAT 1: 710 Q49 V38
Posts: 16
Kudos: 38
 [2]
In three years, Janice will be three times as old as her daughter. Six 01 Sep 2018, 11:07
2
Kudos
Add Kudos
Bookmarks
Bookmark this Post
Let the daughter's age after 3 years be D ; The corresponding age of Janice = 3D
6 years ago (from the present) daughter's age = d-9 ; Janice's age = (d-9)^2

(d-9)^2 + 9 = 3d
(d-6) (d-15) = 0
d = 6 or 15

Janice's present age = 3d - 3 = 15 or 42

15 is not present in the options, thus 42.
avatar
ricksteeves
avatar
Joined: 31 Oct 2020
Last visit: 31 Oct 2020
Posts: 3
Posts: 3
Kudos: 0
In three years, Janice will be three times as old as her daughter. Six 31 Oct 2020, 06:10
Kudos
Add Kudos
Bookmarks
Bookmark this Post
PureVPN Offers 62% Off for a 1-Year Deal (Not so Spooky)

We are offering a discounted deal this Halloween on PureVPN and offering you a big treat.
Available options:

7-Day Trial for only $0.99
1-Year $49.95 - Save 62%
User avatar
bumpbot
User avatar
Non-Human User
Joined: 09 Sep 2013
Last visit: 04 Jan 2021
Posts: 38,967
Own Kudos:
1,117
Posts: 38,967
Kudos: 1,117
In three years, Janice will be three times as old as her daughter. Six 24 Aug 2022, 13:33
Kudos
Add Kudos
Bookmarks
Bookmark this Post
Automated notice from GMAT Club BumpBot:

A member just gave Kudos to this thread, showing it’s still useful. I’ve bumped it to the top so more people can benefit. Feel free to add your own questions or solutions.

This post was generated automatically.
Moderators:
Bunuel
Math Expert
109747 posts
Krunaal
Tuck School Moderator
853 posts