Previous Year Questions

Present age of X, Y and Z is 2A, 2.5B and 3C respectively.

(X - 5)/(Z + 5) = 4/7

(2A - 5)/(3C + 5) = 4/7

14A - 12C = 55 -----(1)

2(Y - 4) = 3(Z - 4) + 14

2Y - 3Z = 10

2*2.5B - 3*3C = 10

5B = 9C + 10 ------(2)

X + Z = Y + C/2

2A + 3C = 2.5B + 0.5C

2.5B = 2A + 2.5C ------(3)

From eqn (2) and (3) -

A - C = 2.5 ----(4)

From eqn (1) and (4) -

A = 12.5, C = 10

B = 20

Sum of present age of Y and Z together = 2.5*20 + 3*10 = 80

Option a - 8(12.5 + 20 + 10)/5 = 68 ≠ 80

Option b - 10(12.5 - 20) + 5 = -70 (not possible)

Option c - 2(12.5 + 20) + 10 = 75 ≠ 80

Option d - 12.5*10 - 2*20 = 85 ≠ 80

Option e - 4*12.5 + 20 + 10 = 80

Hence, option 'e' is correct.