Megan has run many marathons and keeps track of all of her finishing times. At her most recent race, she finished in 297 minutes. That is 10% longer than her previous race. What was Megan's finishing time at the previous race?

해법

M e g an ha s r u n man y ma r a t h o n s an d k ee p s t r a c k o f a ll o f h er f ini s hin g t im es . A t h er m os t rece n t r a ce, s h e f ini s h e d in 297 min u t es . T ha t i s 10% l o n g er t han h er p re v i o u s r a ce . Wha t w a s M e g a n^{'} s f ini s hin g t im e a t t h e p re v i o u s r a ce ?

Amount before addition : 270

솔루션 단계

Translate the problem into an equation:

297 = x + 0.1 x

297 = x + 0.1 x : x = 270

Amount before addition : 270