Quantitative Aptitude Ques 2238
Question: Before 7 yr, the ratio of ages of A and B was 3: 4. After 9 yr, ratio of their ages will be 7: 8. The present age of B will be [SBI (PO) 2012]
Options:
A) 16 yr
B) 19 yr
C) 28 yr
D) 23 yr
E) None of these
Show Answer
Answer:
Correct Answer: D
Solution:
- Let the ages of A and B before 7 yr were $ 3x $ yr and $ 4x $ yr, respectively.
$ \therefore $ Present age of $ A=3x+7 $ and present age of $ B=4x+7 $ Now, according to the question,
$ \therefore $ $ \frac{3x+7+9}{4x+7+9}=\frac{7}{8} $
$ \Rightarrow $ $ 24x+128=28x+112 $
$ \Rightarrow $ $ 4x=16 $
$ \therefore $ $ x=4 $ Hence, present age of $ B=4\times 4+7=16+7=23yr $
BETA
