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 24 teachers, how many pupils must be added so that the ratio becomes 80 : 1?
- 240
- 1920
- 1680
- 10
Answer
A. 240
Solution
Current pupils = 70 × 24 = 1680. Needed = 80 × 24 = 1920. Add 240.
More Ratio and Proportion questions
- ₱20,000 is shared among A, B and C such that A : B = 1 : 6 and B : C = 1 : 3. How much does C receive?
- Paolo and Pia share some money in the ratio 9 : 5. Paolo receives ₱11,760 more than Pia. How much money was shared?
- Two numbers are in the ratio 3 : 4. If 18 is added to each, the ratio becomes 24 : 29. What is the larger of the original numbers?
- The ratio of the number of pupils to teachers in a school is 90 : 1. If there are 30 teachers, how many pupils must be added so that the…
- Alloy X contains gold and copper in the ratio 5 : 3; alloy Y contains them in the ratio 5 : 4. If equal weights of X and Y are melted…
- The present ages of a father and his son are in the ratio 2 : 1. 2 years ago, the ratio was 16 : 7. What is the son's present age?
- Two numbers are in the ratio 2 : 9. If 16 is added to each, the ratio becomes 34 : 97. What is the larger of the original numbers?
- 8 workers can complete a job in 27 days. After working for 12 days, 5 workers leave. How many more days will the remaining workers need to…
- ₱39,360 is shared among A, B and C such that A : B = 2 : 5 and B : C = 1 : 5. How much does C receive?
- A box has red and blue balls in the ratio 7 : 4. After 5 red balls are removed, the ratio becomes 37 : 24. How many blue balls are in the…