Yes, the Property of Equality works for Multiplication
The average speed is the distance divided by the time.
Total distance:
12.8 miles + 17.2 miles = 30 miles
Total time:
noon - 9:00 a.m. = 3 hours
6:00 p.m. - 1:00 p.m. = 5 hours
Total time = 3 hours + 5 hours = 8 hours
average speed = 30 miles / 8 hours = 3.75 miles per hour
17 because you need to multiply
210 because 7th graders washed 12 cars, 8th graders washed 14 cars, 6th graders washed 16 cars. Added all together and multiplied by 5, it equals 210
