40) |
In the afternoon, Judy read 100 pages at the rate of 60 pages per hour; in the
evening, when she was tired, she read another 100 pages at the rate of 40 pages
per hour. In pages per hour, what was her average rate of reading for the day?
Solution
Judy’s average rate of reading is determined by dividing the total number of pages she read (200) by the total amount of time she spent reading. In the afternoon she read for100/60 = 5/3hours, and in the evening for 100/40= 5/2hours, for the total time of 5/3 + 5/2 = 10/6+ 15/6 = 25/6 hours. Her average rate was 200 ÷ 25/6= 200 × 6/25= 48 pages per hour. (B).
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