Question
A and B are two friends. 9 years hence, age of A will
become 2.5 times the present age of B, and the age of B will become 30% less than the present age of A. What is the difference between the present ages of A and B?Solution
ATQ, Let the present age of A and B be x years and y years respectively. According to the question, x+9=2.5y Or, 2.5y−x=9 .... (1) Also, y+9=0.7x Or, 0.7x−y=9 .... (2) On solving equation 1 & 2, x=45 years and y=18 years Required difference = 45−18=27 years
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