Henry took a test with three sections, A, B and C. He spent 1/5 of his time on Section A and 1/3 of the remaining time one Section B. He spent 48 minutes on Section C. How much time did Henry take to complete the test?
Ans: \(90 \text{ minutes.}\)
\(1-{1\over5}={4\over5}\)
\({4\over5}\cdot{1\over3}={4\over15}\)
\({1\over5}+{4\over{15}}={7\over{15}}\)
\(1-{7\over15}={8\over15}\)
\({8\over15}\cdot\text{total time of the test}=48\)
\(\text{total time}=48\cdot{15\over8}=6\cdot15=90\text{ minutes, or } 1 \text{hr. }30\text{ minutes.}\)
