Question

Determine if the following are in proportion.
a) Rs. 40:Rs. 100 = 60kg:150kg
b) 12hours:140mins = 80mins:300mins​

Answer 1

Answer:

(i) We have:

25 cm : 1 m = 25 / 100 (1m = 100 cm)

= (25 ÷ 25) / (100 ÷ 25)

= 1 / 4

Rupees 40 : Rupees 160 = 40 / 160

= (40 ÷ 40) / (160 ÷ 40)

= 1 / 4

Hence, 25 cm : 1m and Rupees 40 : Rupees 160 are in proportion.

(ii) We have:

39 litres : 65 litres = 39 / 65

= (39 ÷ 13) / (65 ÷ 13)

= 3 / 5

6 bottles : 10 bottles = 6 / 10

= 3 / 5

Hence, 39 litres : 65 litres and 6 bottles : 10 bottles are in proportion

(iii) We have:

200 mL : 2.5 L = 200 mL : 2500 mL (1 L = 1000 mL)

= 200 / 2500

= 2 / 25

Rupees 4 : Rupees 50 = 4 / 50

= (4 ÷2) / (50 ÷2)

= 2 / 25

Hence, 200 mL : 2.5 L and Rupees 4 : Rupees 50 are in proportion

(iv) We have:

2 Kg : 80 Kg = 2 / 80

= 1 / 40

25 g : 625 Kg = 25 / 625000 (1 Kg = 1000 g)

= (25 ÷ 25) / (625000 ÷ 25)

= 1 / 25000

Hence, 2 Kg : 80 Kg and 25 g : 625 Kg are not in proportion.

Answer 2

Given.

1) Rs. 40:Rs. 100 = 60kg:150kg

40/100 = 2/5

60/150 = 2/5

Hence in proportion

2)12hours:140mins = 80mins:300mins

12×60/140=36/7

80/300=8/30

Hence not in proportion