Question

Can someone please help me

Answer 1

Explanation:

1) 4 : 7 ? 12 : 21

If product of mean is equal to product of extremes, then they are proportion

Product of extremes = 4*21 = 84

Product of mean = 7 * 12 = 84

Product of extremes = Product of mean

They are in proportion

4 : 7 :: 12 : 21

2) 2 : 3 ? 3: 2

Product of extremes = 2*2 = 4

Product of mean = 3*3 = 9

Product of extremes ≠ Product of mean

They are not in proportion

2 : 3 ≠ 3 : 2

3) 3/4 ? 8/6

3 : 4 ? 8:6

Product of extremes = 3 * 6 = 18

Product of mean = 4 * 8 = 24

Product of extremes ≠ Product of mean

They are not in proportion

3 : 4 ≠ 8 : 6

4) 1/5 ? 5/25

1:5 ? 5 : 25

Product of extremes = 1 * 25 = 25

Product of mean = 5 * 5 = 25

Product of extremes = Product of mean

They are in proportion

1 : 5 :: 5 : 25

Answer 2

1) Yes

Product of Means = Product of Extremes

4 × 21 = 7 × 12

84 = 84

2) No

Product of Means = Product of Extremes

2 × 2 = 3 × 3

4 ≠ 9

3) No

Cross multiplying

3 × 6 = 4 × 8

18 ≠ 32

4) Yes

Cross Multiplying

1 × 25 = 5 × 5

25 = 25