**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

**Solution (a)** 15, 45, 40, 120

. Therefore, ratios are in proportion.

**Solution (b) **33, 121, 9,96

. Therefore, ratios are not in proportion.

**Solution (c) **24, 28, 36, 48

. Therefore, ratios are not in proportion.

**Solution (d) **32, 48, 70, 210

. Therefore, ratios are not in proportion.

**Solution (e)** 4, 6, 8, 12

. Therefore, ratios are in proportion.

**Solution (f)** 33, 44, 75, 100

. Therefore, ratios are in proportion.