Chain Rule Practice Questions

5 questions per page • Detailed step-by-step solutions

Question 21
Easy
50 people went on a picnic with food for 10 days. After 4 days, 10 people left the picnic. For how many more days will the food last?
A 6.5 days
B 7.5 days
C 8 days
D 8.5 days
Correct Answer: B

Explanation:

After 4 days, the remaining food is sufficient for 50 people for (10 - 4) = 6 days = 300 person-days. Remaining people = 50 - 10 = 40 people. The remaining food will last 300 / 40 = 7.5 days.
Question 22
Medium
A certain number of answer sheets can be checked in 12 days, working 5 hours each day, by 9 examiners. For how many hours a day should 4 examiners work to check twice the number of answer sheets in 30 days?
A 8 hours
B 9 hours
C 10 hours
D 12 hours
Correct Answer: B

Explanation:

Using (M1 * D1 * H1) / W1 = (M2 * D2 * H2) / W2: (9 * 12 * 5) / 1 = (4 * 30 * H2) / 2 => 540 = 60 * H2 => H2 = 540 / 60 = 9 hours/day.
Question 23
Easy
If 7 spiders make 7 webs in 7 days, then 1 spider will make 1 web in how many days?
A 1 day
B 7 days
C 14 days
D 49 days
Correct Answer: B

Explanation:

Using (M1 * D1) / W1 = (M2 * D2) / W2: (7 * 7) / 7 = (1 * D2) / 1 => 7 = D2. Thus, 1 spider takes 7 days to make 1 web.
Question 24
Easy
If 2 m, 60 cm cloth is required for one shirt, then the cloth required for 7 shirts is:
A 17 m 80 cm
B 18 m 20 cm
C 18 m 60 cm
D 19 m 10 cm
Correct Answer: B

Explanation:

2 m 60 cm = 2.6 m. Cloth for 7 shirts = 7 * 2.6 = 18.2 m = 18 m 20 cm.
Question 25
Easy
18 men bind 900 books in 10 days. Find how many binders will be required to bind 600 books in 12 days?
A 8 binders
B 10 binders
C 12 binders
D 14 binders
Correct Answer: B

Explanation:

Using (M1 * D1) / W1 = (M2 * D2) / W2: (18 * 10) / 900 = (M2 * 12) / 600 => 1/5 = M2 / 50 => M2 = 10 binders.