Explain simply why 2250 is the correct answer to: Roberto and Valerie are jumping rope at recess. Roberto can skip 4,200 times an hour. Valerie can skip 80 times a minute. If they jump rope for fifteen minutes straight, how many skips will they total?. Explanation:
Roberto skips 70 times per minute because 4,200 / 60 = 70. Together they skip 150 times a minute. They will skip 2,250 times because 150 x 15 = 2,250.