Civil Service Exam Reviewer · Ratio and Proportion · hard
The ratio of the number of pupils to teachers in a school is 80 : 1. If there are 24 teachers, how many pupils must be added so that the ratio becomes 90 : 1?
- 2160
- 240
- 1920
- 10
Answer
B. 240
Solution
Current pupils = 80 × 24 = 1920. Needed = 90 × 24 = 2160. Add 240.
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