Question

The ages of A and B are in the ratio 3:5. Ten years later, the ratio of their ages will be 31:45.
Their present ages are (in years)

Answer 1

Let the present age of A be 3x
and the present age of B be 5x
(As per ratio 3:5)


Ten years later,
A's age= 3x+10
B's age= 5x+10

Given,
After 10 years A : B = 31 : 45
=> (3x+10) : (5x+10) = 31 : 45
=> (3x+10)/(5x+10) = 31/45

Cross Multiply

=> 45(3x+10) = 31(5x+10)
=> 135x+450 = 155x+310
=> 155x-135x = 450-310
=> 20x = 140
=> x = 7

•°•The Present Age of A = 3x = 3(7)= 21 years
and Present Age of B= 5x= 5(7)=35 years



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