Imat 2011 logic/math

Q.34 In 2005, Peter’s age was exactly four times that of his son, Quentin. In 2021, Peter will be
exactly twice Quentin’s age.
What is the difference between their ages?

A 16
B 20
C 24
D 28
E 36

Hi! so for this we can do simultaneous equations.

in 2005 → P = 4Q

in 2021, they both age by 16 years → P+16 = 2(Q+16)

the equations will be
P-4Q=0
P-2Q=16
solve by cancelling P out to find Q.(simultaneous equation method) then substitute Q in the first equation to get P, then you can subtract their ages to find the difference. Hope this helps!

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24

Explanation:

In 2005, let Quentin’s age=q & Peter =4q

In 2021 (i.e 16 years later) ==> (4q+16)=2(q+16)

On solving, we get q=8 & Peter’s age is 8x4=32

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Thank you both ! it makes sense now :slight_smile:

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