<PRE><B>Question 1187160</B>
 A train is going at 1/4 of its usual speed and it take an extra 45 minutes to reach its destination.
 Find its usual time to cover the same distance.
;
let s = the normal speed
then
.25s = the actual speed
and
t = normal time
Change 45 min = .75 hrs
:
write a distance equation, dist = speed*time
st = .25s(t +.75)
st = .25st + .1875s
simplify, divide by s
t = .25t + .1875
t - .25t = .1875
.75t = .1875
t = .1875/.75
t = .25 hrs or 15 min is the normal time
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