Question 747566
Albert raced 4 times as fast as Bernhard.
 In fact, Albert raced 48 miles in 3 hours less than it took Bernhard to race 30 miles.
 How fast did each of them race?
 What were the times of each racer?
:
Let s = B's racing speed
then
4s = A's speed
:
Write a time equation; time = dist/speed
:
B's time - A's time = 3 hrs
{{{30/s}}} - {{{48/(4s)}}} = 3
mult by 4s to clear denominators, resulting in:
4(30) - 48 = 3(4s)
120 - 48 = 12s
72 = 12s
s = 72/12
s = 6 mph, is B's speed
then
4(6) = 24 mph is A's speed
:
Their times
30/6 = 5 hrs for B
48/24 = 2 hrs for A
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differs: 3 hrs