Question

5 years ago the sum of the ages of father and mother was x years.After 10 years the sum of the ages of their 3 children becomesy years. Find the sum of the present ages of all of them.

OPTIONS
a)x+y-20
b)x-y+20
c)x+y+40
d)x+y-40​

Answer 1

Step-by-step explanation:

let present age of father mother and children's be f,m,c1,c2,c3 respectively

then

f-5+m-5=x

f+m= x+10---equ1

(c1+10)+(c2+10)+(c3+10)=y0c1+c2+c3=y-30----equ2

add equation 1&2

we get

f+m+c1+c2+c3=x+10+y-30

f+m+c1+c2+c3=x+y-20