Let's solve each question step by step and provide explanations.
---
I. CHOOSE THE BEST ANSWER (5 Marks)
####
1. The equivalent ratio of 2:7 is ________
We need to find a ratio that simplifies to 2:7.
Check each option:
- a. 7:2 → Not equivalent (it's the reverse)
- b. 6:14 → Divide both by 2 → 3:7 → Not equal to 2:7
- c. 4:14 → Divide by 2 → 2:7
✔ Yes!
- d. 20:35 → Divide by 5 → 4:7 → Not equal
✔ Answer: c. 4:14
---
####
2. The simplest form of the ratio of 12:6 is ________
Divide both numbers by their GCD (6):
12 ÷ 6 = 2
6 ÷ 6 = 1
So, 12:6 = 2:1
✔ Answer: d. 2:1
---
####
3. The ratio of the number of sides of a triangle to the number of sides of a square is ________
- Triangle has 3 sides
- Square has 4 sides
Ratio = 3:4
✔ Answer: b. 3:4
---
####
4. The simplest form of the ratio of 2m to 25 cm is ________
First, convert units to be the same.
2 m = 200 cm
Now ratio: 200 cm : 25 cm
Simplify:
200 ÷ 25 = 8
25 ÷ 25 = 1
So, 8:1
✔ Answer: c. 8:1
---
####
5. If the cost of 3 dolls is Rs. 45, then the cost of 5 dolls is Rs. ___
Cost of 1 doll = 45 ÷ 3 = Rs. 15
Cost of 5 dolls = 15 × 5 = Rs. 75
✔ Answer: a. 75
---
II. FILL IN THE BLANKS (5 Marks)
####
6. 5:____ :: 30:18
This is a proportion:
5 : x :: 30 : 18
Using cross multiplication:
5 × 18 = 30 × x
90 = 30x
x = 90 ÷ 30 = 3
✔ Answer: 3
---
####
7. Ratio of 5 minutes to 8 minutes is ______
Since units are same (minutes), ratio is simply:
5:8
✔ Answer: 5:8
---
####
8. If Rs. 50 is divided among P and Q in the ratio 3:2, then Q’s share is Rs. ____
Total parts = 3 + 2 = 5
Each part = 50 ÷ 5 = Rs. 10
Q’s share = 2 parts = 2 × 10 = Rs. 20
✔ Answer: 20
---
####
9. The two quantities in a ratio should be of the _____ unit.
For a meaningful ratio, both quantities must be in the
same unit.
✔ Answer: same
---
####
10. If a : b :: c : d, then ad = ______
This means:
a/b = c/d
Cross-multiplying:
a × d = b × c
So,
ad = bc
✔ Answer: bc
---
✔ Final Answers Summary:
I. Choose the best answer:
1. c. 4:14
2. d. 2:1
3. b. 3:4
4. c. 8:1
5. a. 75
II. Fill in the blanks:
6. 3
7. 5:8
8. 20
9. same
10. bc
---
Let me know if you'd like this formatted as a printable answer sheet!
Parent Tip: Review the logic above to help your child master the concept of ratio and proportion worksheet pdf.