The ages of Krish and Vaibhav are in the proportion of 3 : 5. After 9 years, the proportion of their ages will be 3 : 4. Then the current age of Vaibhav is: Choose the correct choice from the following choices:  A) 10  B) 13  C) 15  D) 18  E) 19
Explanation:   Krish’s age = 3A and Vaibhav’s age = 5A =(3A + 9)/(5A + 9)=3/4   =&gt; 4 (3A + 9) = 3 (5A + 9)   =&gt; A = 3   Therefore, Vaibhav’s age = 15 years. Answer: 15
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The ages of Krish and Vaibhav are in the proportion of 3 : 5. After 9 years, the proportion of their ages will be 3 : 4. Then the current age of Vaibhav is: