Civil Service Exam Reviewer · Ratio and Proportion · hard
The ratio of the number of pupils to teachers in a school is 70 : 1. If there are 32 teachers, how many pupils must be added so that the ratio becomes 80 : 1?
- 2560
- 2240
- 10
- 320
Answer
D. 320
Solution
Current pupils = 70 × 32 = 2240. Needed = 80 × 32 = 2560. Add 320.
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