Question 515278
Let {{{x}}} = increase
{{{ 100 + x = (7/5)*( 60 + x ) }}}
{{{ 500 + 5x = 7*( 60 + x ) }}}
{{{ 500 + 5x = 420 + 7x }}}
{{{ 2x = 80 }}}
{{{ x = 40 }}}
The increase is rs40
check:
{{{ 100 + 40 = (7/5)*( 60 + 40 ) }}} 
{{{ 140 = (7/5)*100 }}}
{{{ 700 = 700 }}}
OK