CLASS-6 MATHS CHAPTER 12 (EXERCISE -12.2)

                                                                 CHAPTER-12

EXERCISE-12.2 

                              

Question 1:

Determine if the following are in proportion.

(a) 15, 45, 40, 120 (b) 33, 121, 9, 96

(c) 24, 28, 36, 48 (d) 32, 48, 70, 210

(e) 4, 6, 8, 12 (f) 33, 44, 75, 100

Answer:

(a) 15, 45, 40, 120

Therefore, 15: 45 = 40: 120

Hence, these are in proportion.

(b) 33, 121, 9, 96

Therefore, 33: 121 ≠ 9: 96

Hence, these are not in proportion.

(c) 24, 28, 36, 48

Therefore, 24: 28 ≠ 36: 48

Hence, these are not in proportion.

(d) 32, 48, 70, 210

Therefore, 32: 48 ≠ 70: 210

Hence, these are not in proportion.

(e) 4, 6, 8, 12

Therefore, 4: 6 = 8: 12

Hence, these are in proportion.

(f) 33, 44, 75, 100

Therefore, 33: 44 = 75: 100

Hence, these are in proportion.

Question 2:

Write True (T) or False (F) against each of the following statements:

(a) 16:24::20:30 (b) 21:6::35:10

(c) 12:18::28:12 (d) 8:9::24:27

(e) 5.2:3.9::3:4 (f) 0.9:0.36::10:4

Answer:

(a) 16: 24:: 20: 30

Therefore, 16: 24 = 20: 30

Hence, True

(b) 21: 6:: 35: 10

Therefore, 21: 6 = 35: 10

Hence, True

(c) 12: 18:: 28: 12

Therefore, 12: 18 ≠ 28: 12

Hence, False

(d) 8: 9:: 24: 27

As,

Therefore, True

(e) 5.2: 3.9:: 3: 4

As ,

Therefore, 5.2: 3.9 ≠ 3: 4

Hence, False

(f) 0.9: 0.36:: 10: 4

Therefore, 0.9: 0.36 = 10: 4

Hence, True

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Question 3:

Are the following statements true?

(a) 40 persons: 200 persons = Rs 15: Rs 75

(b) 7.5 litres: 15 litres = 5 kg: 10 kg

(c) 99 kg: 45 kg = Rs 44: Rs 20

(d) 32 m: 64 m = 6 sec: 12 sec

(e) 45 km: 60 km = 12 hours: 15 hours

Answer:

(a) 40 persons: 200 persons = Rs 15: Rs 75

True

(b) 7.5 l: 15 l = 5 kg: 10 kg

True

(c) 99 kg: 45 kg = Rs 44: Rs 20

True

(d) 32 m: 64 m = 6 sec: 12 sec

True

(e) 45 km: 60 km = 12 hrs: 15 hrs

False

CLASS-6 MATHS CHAP-12 Exercise-12.1

CHAPTER -12  

RATIO AND PROPORTION 

EXERCISE-12.1

Question 1:

There are 20 girls and 15 boys in a class.

(a) What is the ratio of number of girls to the number of boys?

(b)What is the ratio of number of girls to the total number of students in the class?

Answer:

Number of girls = 20

Number of boys = 15

Total number of students = 20 + 15 = 35

(a) Ratio of number of girls to boys =

(b) Ratio of number of girls to total students =

Question 2:

Out of 30 students in a class, 6 like football, 12 like cricket and remaining like tennis. Find the ratio of

(a) Number of students liking football to number of students liking tennis.

(b) Number of students liking cricket to total number of students.

Answer:

Number of students who like football = 6

Number of students who like cricket = 12

Number of students who like tennis = 30 − 6 − 12 = 12

(a) Ratio of the number of students liking football to the number of students liking tennis =

(b) Ratio of the number of students liking cricket to the total number of

students =

Question 3:

See the figure and find the ratio of

(a) Number of triangles to the number of circles inside the rectangle.

(b) Number of squares to all the figures inside the rectangle.

(c) Number of circles to all the figures inside the rectangle.

Answer:

Number of triangles = 3

Number of circles = 2

Number of squares = 2

Total number of figures = 7

(a) Ratio of the number of triangles to the number of circles =

(b) Ratio of the number of squares to all the figures in the rectangle =

(c) Ratio of the number of circles to all the figures in the rectangle =

Question 5:

Fill in the following blanks:

 [Are these equivalent ratios?]

Answer:

Therefore, 5, 12, 25 will come in the blanks respectively.

Yes, all these are equivalent ratios.

Question 9:

There are 102 teachers in a school of 3300 students. Find the ratio of the number of teachers to the number of students.

Answer:

Ratio required =

Question 10:

In a college, out of 4320 students, 2300 are girls. Find the ratio of

(a) Number of girls to the total number of students.

(b) Number of boys to the number of girls.

(c) Number of boys to the total number of students.

Answer:

Total number of students = 4320

Number of girls = 2300

Number of boys = 4320 − 2300 = 2020

(a) Required ratio =

(b) Required ratio =

(c) Required ratio =