Joey solves math problems at a rate of 3 problems every 7 minutes. If he continues work at the same rate, how long will it take Joey to solve 45 problems?

1 Answer
Mar 10, 2018

#105# minutes

Explanation:

Well, he can solve #3# problems in #7# minutes. Let #x# be the time he has to solve #45# problems. Then, we got

#(3 \ "problems")/(7 \ "minutes")=(45 \ "problems")/x#

#:.x=(45color(red)cancelcolor(black)"problems")/(3color(red)cancelcolor(black)"problems")*7 \ "minutes"#

#=15*7 \ "minutes"#

#=105 \ "minutes"#