Question

Randall is 140 miles away from Gregory. They are traveling towards each other. If Gregory travels 4 mph faster than Randall and they meet after 7 hours, how fast was each traveling?

Answer 1

Answer:

8 mph, 12 mph

Explanation:

t = Time taken = 7 hours

x = Speed of Randall

x+4 = Speed of Gregory

The distance they both will travel together is 140 miles if they start at the same time.

$Distance=Speed\times time$

$(x+4)t+xt=140\\\Rightarrow (x+4)7+7x=140\\\Rightarrow 7x+28+7x=140\\\Rightarrow 28+14x=140\\\Rightarrow x=\dfrac{140-28}{14}\\\Rightarrow x=8\ mph$

The speed of Randall is 8 mph

The speed of Gregory is 8+4 = 12 mph