Civil Service Exam Reviewer · Ratio and Proportion · hard
The ratio of the number of pupils to teachers in a school is 60 : 1. If there are 32 teachers, how many pupils must be added so that the ratio becomes 70 : 1?
- 320
- 2240
- 1920
- 10
Answer
A. 320
Solution
Current pupils = 60 × 32 = 1920. Needed = 70 × 32 = 2240. Add 320.
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