# One year ago, the ratio of Gaurav’s and Sachin’s age was 6 : 7 respectively. Four years hence, this ratio would become 7 : 8. How old is Sachin ?

$\par&space;Let&space;Gaurav's&space;and&space;Sachin's&space;ages&space;one&space;year&space;ago&space;be&space;6x&space;and&space;7x&space;years&space;respectively.$

$\par&space;Gaurav's&space;age&space;4&space;years&space;hence&space;=&space;(6x&space;+&space;1)&space;+&space;4&space;=&space;(6x&space;+&space;5)&space;years$

$\par&space;Sachin's&space;age&space;4&space;years&space;hence&space;=&space;(7x&space;+&space;1)&space;+&space;4&space;=&space;(7x&space;+&space;5)&space;years$

$\frac{6x&space;+&space;5}{7x&space;+&space;5}&space;=&space;\frac{7}{8}$

$8(6x&space;+&space;5)&space;=&space;7(7x&space;+&space;5)$

$48x&space;+&space;40&space;=&space;49x&space;+&space;35$

$x&space;=&space;5$

$\par&space;Hence&space;Sachin's&space;present&space;age&space;=&space;(7x&space;+&space;1)&space;=&space;36&space;years$