Question

Mary is three times older than nandhini.after 10 years the sum of their ages will be 80. find their present ages

Answer 1

Let Mary's age be x

and Nandhini's be y

so, 3x=y [Call this as 1st equation]

after 10 years

Mary=x+10

Nandhini=y+10

Sum of their ages

x+10 + y + 10=80

x=15[after substituting 1st equation and solving]

3x=y[1st equation]

3 x 15 = y

45 = y

Mary age = 15

Nandhini age = 45