SOLUTION: Grace's average driving speed is 10 mph faster than Tom's. In the same length of time, it takes Grace to drive 280 miles, Tom only drives 230. What is Grace's average speed?

Question 870877: Grace's average driving speed is 10 mph faster than Tom's. In the same length of time, it takes Grace to drive 280 miles, Tom only drives 230. What is Grace's average speed?
Answer by JulietG(1812) (Show Source): You can put this solution on YOUR website!
What is the difference in the distance between Grace and Tom? 280-230=50
What is the difference in the RATE of speed? 10 mph [given]
If she drives 50 miles further at a rate of 10mph faster, they drive for five hours (50/10)
If she drives 280 miles in 5 hours, her speed is 280/5, or 56 mph
If he drives 230 miles in 5 hours, his speed is 230/5, or 46 mph
The average is her speed + his speed, divided by 2. (56+46)/2, or 102/2, or 51 mph.
RELATED QUESTIONS
Grace;s average driving speed is 3 mph faster than Thelma's. In the same length of time... (answered by checkley71)

Please show me how to solve this problem Richard's average driving speed is 3 miles... (answered by ankor@dixie-net.com)

Richard�s average driving speed is 6 kilometers per hour faster than Thor�s. In the same... (answered by lwsshak3)

Thelma's average driving speed is 3 miles per hour faster than Doug's. In the same... (answered by josmiceli)

Thelma's average driving speed is 15 miles per hour faster than Kirk's. in the same... (answered by stanbon)

Richard's average driving speed is 4 miles per hour faster than Kirk's. In the same... (answered by Paul)

I'd greatly appreciate it if some one could help me. Thanks!! Richard's average driving... (answered by edjones)

Richard's average driving speed is 23 km per hour faster than Kirk's. In the same length (answered by checkley77)

Thor's average driving speed is 25 km/hr faster than Kirk's. In the same length of time... (answered by josmiceli)