Niki runs at a rate of 800 ft. per minute. Jeff runs at the rate of 900 ft. per minute. If Niki starts 500 feet ahead of Jeff, how many minutes does it take Jeff to catch up with her.
Jeff runs 900-800 = 100 fet per minute faster than Nikaroo
Jeff will cover 500 ft in 500ft/ 100ft/min = 5 minutes