The swimming pool in an exclusive subdivision has 4 inlet pipes
and one outlet pipe. The pool always has 250 cubic meters of
water in the bottom. If every inlet pipe brings in 25 cubic meters
of water per hour, and the outlet pipe drains 10 cubic meters per
hour, the relationship between the volume of water in cubic meters
V and the time in hours + when all the pipes are open is given by
V(1) = (4×25-10)t + 250 = 90% + 250 where + > 0. How much
time is needed for the pool to have 655 cubic meters of water?