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