Civil Service Exam Reviewer · Ratio and Proportion · hard
The ratio of the number of pupils to teachers in a school is 90 : 1. If there are 16 teachers, how many pupils must be added so that the ratio becomes 100 : 1?
- 1600
- 1440
- 160
- 10
Answer
C. 160
Solution
Current pupils = 90 × 16 = 1440. Needed = 100 × 16 = 1600. Add 160.
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