Question 1206959
x, minutes of time past 2:30 pm
y, amount of tank full


Points are 
2:30 pm,  (0, 3/5)
3:25 pm,  (55, 2/7)


Equation can start as {{{y=((2/7-3/5)/55)x+3/5}}}

.
steps lead to
.
{{{y=-x/(5*35)+3/5}}}.


For how much time, x, past 2:30 pm is tank empty, y=0?
{{{x/(3*35)=3/5}}}


{{{x=105}}} {{{minutes}}}
which is 1 hour 45 minutes...


Add that amount of time to 2:30 pm on the clock.