Respuesta :
Answer: 20 mph
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Explanation:
x = Jose's speed in mph
x+35 = Kayla's speed since she drives 35 mph faster than Jose
Jose gets a 2.1 hour head start and it takes Kayla 1.2 hours to reach him. So this means Jose has been driving for 2.1+1.2 = 3.3 hours when Kayla reaches him. The distance he travels is
distance = rate*time
d = r*t
d = x*3.3
d = 3.3x
while Kayla's distance equation is
d = r*t
d = (x+35)*1.2
d = 1.2x+42
Since Kayla meets up with Jose at the 1.2 hour mark, this means the two distances they travel is the same. Set their distance expressions equal to one another. Solve for x.
3.3x = 1.2x+42
3.3x-1.2x = 42
2.1x = 42
x = 42/(2.1)
x = 20
Jose's speed is 20 mph, while Kayla's speed is x+35 = 20+35 = 55 mph.
Jose's fairly slow speed is probably due to a number of factors such as heavy traffic, icy roads, or poor visibility. Kayla probably got a bit of a break with more favorable conditions.
Since Jose travels at 20 mph and does so for 3.3 hours, he travels d = r*t = 20*3.3 = 66 miles. Kayla travels d = r*t = 55*1.2 = 66 miles as well. We get the same number each time to help confirm the answer.
