Ajeep and bmw enter a highway running east-west at the same exit heading in opposite directions. the jeep entered the highway 30 minutes before the bmw did, and traveled 7 mph slower than the bmw. after 2 hours from the time the bmw entered the highway, the cars were 306.5 miles apart. find the speed of each car, assuming they were driven on cruise control.

Recall you d = rt, distance = rate * time

when the BMW has been running for 2hrs, the Jeep has been running for 2.5hrs, because it started off the exit 30minutes(0.5hr) before the BMW.

if the rate of the BMW is say "r", then the rate of the Jeep is "r - 7", slower by 7mph.

now, we know after the Jeep was running for 2.5hrs and the BMW was running for 2hrs, they were both apart by 306.5miles, so, say if the Jeep travelled a distance of "d", then the BMW travelled the slack from the 306.5, or "306.5 - d".



solve for "r" to get the rate of the BMW.

what about the Jeep's? well, the Jeep is just r - 7.