Question 570716
{{{ 12*12 = 144 }}} ft2 of area
Jane's rate of painting is {{{ 144/(3/4) }}} ft2/hr
{{{ 144/(3/4) = (4/3)*144 }}}
{{{ (4/3)*144 = 192 }}} ft2/hr
In units:
( ft2 / ( ft2/hr) = hrs 
{{{ 15*16 = 240 }}} ft2
{{{ 240 / 192 = 1.25 }}}
It will take her 1 hour and 15 min to 
paint the 15x16 ft2 wall