Students can download Maths Chapter 3 Ratio and Proportion Ex 3.3 Questions and Answers, Notes, Samacheer Kalvi 6th Maths Guide Pdf helps you to revise the complete Tamilnadu State Board New Syllabus, helps students complete homework assignments and to score high marks in board exams.

## Tamilnadu Samacheer Kalvi 6th Maths Solutions Term 1 Chapter 3 Ratio and Proportion Ex 3.3

Question 1.

Fill in the blanks.

(i) 3 : 5 :: …….. : 20

(ii) ……… : 24 :: 3 : 8

(iii) 5 : …….. :: 10 : 8 :: 15 : ………

(iv) 12 : ……… :: ………. :: 4 = 8 : 16

Solution:

(i) 12

Hint:

5x = 3 × 20 ⇒ x = 12

(ii) 9

8x = 24 × 3 ⇒ x = 9

(iii) 4, 12

Hint:

10x = 8 × 5 = 40 ⇒ x = 4

10y = 8 × 15 = 120 ⇒ y = 12

(iv) 24, 2

Hint:

16y = 8 × 4 ⇒ y = 2

12 × 4 = 2x ⇒ x = 24

Question 2.

Say True or False.

(i) 2 : 7 : : 14 : 4

(ii) 7 Persons are to 49 Persons as 11 kg is to 88 kg

(iii) 10 books are to 15 books as 3 books are to 15 books.

Solution:

(i) False

Hint:

7 × 14 ≠ 4 × 2

98 ≠ 8

(ii) False

Hint:

7 : 49 :: 11 : 48

49 × 11 ≠ 7 × 48

539 ≠ 336

(iii) False

Hint:

10 : 15 :: 3 : 5

\(\frac{10}{15}=\frac{5 \times 2}{5 \times 3}=\frac{2}{3} \Rightarrow \frac{3}{5}=\frac{3}{5}\)

Question 3.

Using the numbers 3, 9, 4, 12 write two ratios that are in proportion.

Solution:

(i) 3, 9, 4, 12

Here product of extremes = 3 × 12 = 36

Product of means = 9 × 4 = 36

3 : 9 : : 4 : 12

(ii) Also if we take 9, 3, 12, 4

Product of extremes = 9 × 4 = 36

Product of means = 3 × 12 = 36

9 : 3 : : 12 : 4

Question 4.

Find whether 12, 24,18, 36 are in order that can be expressed as two ratios that are in proportion.

Solution:

Yes, 12 : 24 : : 18 : 36

Because product of extremes 12 × 36 = 432

Product of means = 24 × 18 = 432

12 : 24 :: 18 : 36.

Question 5.

Write the mean and extreme terms in the following ratios and check whether they are in proportion.

(i) 78 liters is to 130 liters and 12 bottles are to 20 bottles

(ii) 400 gm is to 50 gm and 25 rupees is to 625 rupees

Solution:

(i) 78 : 130 :: 12 : 20

Extreme terms are 78 and 20.

Mean terms are 130 and 12.

Product of Extremes = 78 × 20 = 1560

Product of Means = 130 × 12 = 1560

Product of Extremes = Product of means

It is in proportion.

(ii) 400 : 50 : : 25 : 625

Product of extremes = 400 × 625 = 2,50,000

Product of means = 50 × 25 = 1250

Here product of extremes ≠ product of means

400 : 50 and 25 : 625 are not in proportion.

Question 6.

America’s famous Golden Gate bridge is 6480 ft long with 756 ft tall towers. A model of this bridge exhibited in a fair is 60 ft long with 7 ft tall towers. Is the model in proportion to the original bridge?

Solution:

6480 : 756, 60 : 7

Product of the means = 756 × 60 = 45360

Product of the extremes = 6480 × 7 = 45360

ad = bc

∴ They are in proportion

Objective Type Questions

Question 7.

Which of the following ratios are in proportion?

(a) 3 : 5, 6 : 11

(b) 2 : 3, 9 : 6

(c) 2 : 5, 10 : 25

(d) 3 : 1, 1 : 3

Solution:

(c) 2 : 5, 10 : 25

Hint:

2 × 25 = 5 × 10

⇒ 50 = 50

Question 8.

If the ratios formed using the numbers 2, 5, x, 20 in the same order are in proportion, then ‘x’ is

(a) 50

(b) 4

(c) 10

(d) 8

Solution:

(d) 8

5x = 2 × 20 ⇒ x = 8

Question 9.

If 7 : 5 is in proportion to x : 25, then ‘x’ is

(a) 27

(b) 49

(c) 35

(d) 14

Solution:

(c) 35

Hint:

5x = 7 × 25 ⇒ x = 35