Andrew will be half as old as Larry in 3 years. Andrew will also be on

Question

Andrew will be half as old as Larry in 3 years. Andrew will also be one-third as old as Jerome in 5 years. If Jerome is 15 years older than Larry, how old is Andrew?

A. 6
B. 8
C. 19
D. 26
E. 34

Kudos for a correct  solution .

Taurus · Answer

The answer is B.

In three years Andrew will be 11 (8+3=11), and Larry will be 22 (11*2=22). That means Larry is now 19 (22-3=19).
In five years Andrew will be 13 (8+5=13), and Jerome will be (13*3=39). That means Jerome is now 34 (39-5=34).

Jerome is 15 years older than Larry which corresponds to the two previous calculations (34-19=15).

Andrew now is 8 years old and the correct answer is B. :-D

balamoon · Answer

Andrew will be half as old as Larry in 3 years. Andrew will also be one-third as old as Jerome in 5 years. If Jerome is 15 years older than Larry, how old is Andrew?

A. 6
B. 8
C. 19
D. 26
E. 34

Solution -
Given that, Andrew+3 = (Larry+3)/2 .....1

Andrew+5 = (Jerome+5)/3 ..............2

Jerome = Larry+15 ................3

Substitute 3 in 2 ---> 3*Andrew - 5 = Larry ------------4

Substitute 4 in 1 ---> A = 8 years.

ANS B.

lipsi18 · Answer

let age of Andrew =x, Larry =y 7 J = Z
we have (X+3) =1/2 *(y+3) so we have 2X-y =-3 ---1
we have (X+5) =1/3 * (z+5) ; => 3x-z=-10 ---2
adding above 2 equation we get, x+y-z =-7 ----3
we have z =15+y
from equation 3 and 4 we get x=8

Hence answer is B
Thanks,

adityadon · Answer

did using options .. 
started with B and came out to be correct

Andrew today = 8 , so 3 years later = 11 , so Larry after 3 years = 22
So larry today = 19
Also andrw after 5 years = 13 , so jeromi after 5 years = 39 
So jeromi today 34
 difference betweeb larry and jeromi = 15 ... so my assumed value of andrew age is correct. 
Answer B

Bunuel · Answer

MANHATTAN GMAT OFFICIAL SOLUTION:

Let A = Andrew s age now, let L = Larrys age now, and let J = Jerome s age now.

Andrew will be half as old as Larry in 3 years --> 2(A + 3) = (L + 3)
Andrew will also be one-third as old as Jerome in 5 years --> 3(A + 5) = J + 5
If Jerome is 15 years older than Larry --> J = L + 15

You ultimately need to find the value of A. If you replace J in the second equation with (L + 15), both the first and second equations will contain the variables A and L:

3(A + 5) = J + 5 --> 3(A + 5) = (L + 15) + 5

Simplify the first two equations:
2(A + 3) = (L + 3); 3(A + 5) = (L + 15) + 5
2A + 6 = L + 3; 3A + 15 = L + 20

If you subtract the first equation from the second equation, you can cancel out Z, which will allow you to solve for A:
3A + 15 = L + 20
-(2A + 6 = L + 3)
_____________
A + 9 = 17
A = 8

Answer: B.

ScottTargetTestPrep · Answer

We can create the equations:

A + 3 = (1/2)(L + 3)

2A + 6 = L + 3

2A + 3 = L

and

A + 5 = (1/3)(J + 5)

3A + 15 = J + 5

3A + 10 = J

and

J = L + 15

Substituting L + 15 for J in the equation 3A + 10 = J, we have:

3A + 10 = L + 15

3A - 5 = L

Substituting 3A - 5 for L in the equation 2A + 3 = L, we have:

2A + 3 = 3A - 5

8 = A

Answer: B

bumpbot · Answer

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