The ratio of the present ages of P and Q is 3 : 4. Five years ago, the ratio of their ages was 5 : 7. Find their present ages.
Answer: B
As the ratio of their present ages is 3 : 4 , let their present ages be \(3x\) and \(4x\) respectively.
So, 5 years ago, as the ratio of their ages was 5 : 7, we can write \((3x-5) : (4x-5) = 5 : 7\)
Solving, we get \(x=10\)
Hence, their present ages are \(3x = 30\) and \(4x=40\)