human
Brody’s calculator can run for 60 hours on a full battery. Brody has used three quarters of its battery up, and he is about to take a two-hour math exam that will require his calculator the whole time. How many hours of battery will Brody’s calculator have left?
assistant
How many hours of battery does Brody’s calculator have left? ** Brody’s calculator has 60 * 1/4 = 60 / 4 = <<60*1/4=15>>15 hours of battery left.
How many hours of battery will Brody’s calculator have left after his math exam? ** After his 2-hour math exam, Brody’s calculator will have 15 - 2 = <<15-2=13>>13 hours of battery left.
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