Question

Kong took %15, percent fewer seconds than Nolan took to complete his multiplication timed test. Kong took 85seconds. How many seconds did Nolan take?

Answer 1

Nolan took x seconds.
Kong took 15% less than x seconds.
100% - 15% = 85%
Kong took 85% of Nolan;s time, so Kong took 85% * x = 0.85x seconds.
Kong took 85 seconds, so 0.85x = 85

0.85x = 85

Divide both sides by 0.85.

x = 100

Answer: Nolan took 100 seconds.