94. Before 7 years, the ratio of ages of A and Bwas 3:4. After 9 years

1.	94. Before 7 years, the ratio of ages of A and Bwas 3:4. After 9 years, ratio of their ages will be7:8. The present age of B will be(A) 16 years(B) 19 years(C) 28 years(D) 23 years
Answer» Let the ages of A and B before 7 yr were 3x yr and 4x yr, respectively. Present age of A = 3x + 7 and present age of B = 4x + 7 Now, according to the question, 3x+7+94x+7+9=783x+7+94x+7+9=78 24x + 128 =28x + 112 4x = 16 x = 4 Hence, present age of B = 4 x 4+ 7 = 16 + 7= 23yr

94. Before 7 years, the ratio of ages of A and Bwas 3:4. After 9 years, ratio of their ages will be7:8. The present age of B will be(A) 16 years(B) 19 years(C) 28 years(D) 23 years

Answer»

Let the ages of A and B before 7 yr were 3x yr and 4x yr, respectively.

Present age of A = 3x + 7 and present age of B = 4x + 7

Now, according to the question,

3x+7+94x+7+9=783x+7+94x+7+9=78

24x + 128 =28x + 112

4x = 16

x = 4

Hence, present age of B = 4 x 4+ 7 = 16 + 7= 23yr