Question

Present ages of $XandY$ are in the ratio $5:6$ respectively. Seven years hence this ratio will become $6:7$ respectively. What is $X^{\prime }s$ present age ?

• A. $35$ years
• B. $42$ years
• C. $49$ years
• D. Can't be determined

Answer 1

The correct option is A $35$ years

As per question,
$\frac{x}{y}=\frac{5}{6}$
$6x=5y$
$6x-5y=0$ multiply eq by 6.
$36x-30y=0$ ...eq 1
$\frac{x+7}{y+7}=\frac{6}{7}$
$7x+49=6y+42$
$7x-6y=-7$ ...multiply eq by 5.
$35x-30y=-35$.... eq 2
eq1-eq2
$x=35$
Answer (A) 35 Years