Chain Rule
1. If 5 workers can build 3 walls in 6 days, how many days will 10 workers take to build 6 walls?
A. 3 days
B. 6 days
C. 9 days
D. 12 days
B. 6 days
2. If 8 machines produce 120 units in 5 hours, how many machines are needed to produce 300 units in 10 hours?
A. 5
B. 8
C. 10
D. 12
C. 10
3. If 6 pumps fill 9 tanks in 3 hours, how many pumps will fill 15 tanks in 5 hours?
A. 5
B. 6
C. 8
D. 10
B. 6
4. If 4 books cost ₹600, how much will 10 books cost if the price per book decreases by ₹10?
A. ₹1,200
B. ₹1,300
C. ₹1,400
D. ₹1,500
C. ₹1,400
5. A hostel has food for 40 students for 30 days. If 10 more students join, how long will the food last?
A. 20 days
B. 24 days
C. 27 days
D. 30 days
B. 24 days
6. A car travels 360 km on 30L petrol. How far will it travel on 45L if efficiency improves by 20%?
A. 540 km
B. 600 km
C. 648 km
D. 720 km
C. 648 km
7. 20 workers build a wall in 10 days. If 5 workers are 20% more efficient, how many days will they take?
A. 8 days
B. 10 days
C. 12 days
D. 15 days
A. 8 days
8. A farmer harvests 200kg wheat from 5 acres in 4 days. How many acres are needed to harvest 600kg in 6 days?
A. 8 acres
B. 10 acres
C. 12 acres
D. 15 acres
B. 10 acres
9. Printing 500 books costs ₹25,000. How much will printing 800 books cost if the price per book drops by 10%?
A. ₹32,000
B. ₹36,000
C. ₹40,000
D. ₹44,000
B. ₹36,000
10. A pipe fills a tank in 8 hours. If two similar pipes are used, how long will it take?
A. 2 hours
B. 4 hours
C. 6 hours
D. 8 hours
B. 4 hours