Question

Neil is 4 years older than Andrea. If Neil was twice as old as Andrea four years ago, how old was Andrea?

Answer 1

Answer:

Neil's age is 12 and the age of Andrea is 8.

Step-by-step explanation:

Let

x ---> Neil's age

y ---> Andrea's age

we know that

Neil is 4 years older than Andrea

so

$x=y+4$ -----> equation A

Neil was twice as old as Andrea four years ago

so

$x-4=2(y-4)$

$x-4=2y-8\\x-2y=-8+4$

$x-2y=-4$ ----> equation B

substitute equation A in equation B

$y+4-2y=-4$

solve for y

$2y-y=4+4\\y=8$

Find the value of x

$x=8+4=12$

therefore

Neil's age is 12 and the age of Andrea is 8.