Question

1. Determine which of the following are in proportion
(a) 18, 36, 9, 18 (b) 14, 35, 16, 40
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Answer 1

Answer:

a) 18,36,9,18... is correct answer

Answer 2

a) 18, 36, 9 and 18 are in a proportion.

b) 14, 35, 16 and 40 are in a proportion.

Step-by-step explanation:

a) We have,

18, 36, 9 and 18 are in a proportion.

18 : 36 : : 9 : 18

To find, 18, 36, 9 and 18 are in a proportion or not.

We know that,

a : b : : c : d

Product of means = Product of extremes

a × d = b × c

∴ a × d = 18 × 18 = 324

Also,

b × c = 36 × 9 = 324

∴ a × d = b × c = 324

Thus, 18, 36, 9 and 18 are in a proportion.

b) We have,

14, 35, 16 and 40 are in a proportion.

14 : 35 : : 16 : 40

To find, 14, 35, 16 and 40 are in a proportion or not.

We know that,

a : b : : c : d

Product of means = Product of extremes

a × d = b × c

∴ a × d = 14 × 40 = 560

Also,

b × c = 35 × 16 = 560

∴ a × d = b × c = 560

Thus, 14, 35, 16 and 40 are in a proportion.