Question 1146053
Mary's rate  r
Peter's rate (1/2.5)r=0.4r


{{{r+0.4r=1/12.5}}}

{{{1.4r=1/12.5}}}

{{{r=1/(1.4*12.5)}}}


TIME in hours is  {{{1.4*12.5=highlight(highlight(17.5))}}}