Divide 7.2 by 0.3.

Divide 7.2 by 0.3.

• A. 24
• B. 8
• C. 2.4
• D. 120

Answer: (A)

Dividing by a decimal works best by removing the decimals first. If we multiply both numbers by the same power of 10, the value doesn’t change. Here, multiply top and bottom by 10: 7.2 × 10 = 72 and 0.3 × 10 = 3, so it becomes 72 ÷ 3. Since 72 divided by 3 is 24, the result is 24. Think of 7.2 as 72 tenths and 0.3 as 3 tenths; asking how many 3-tenths fit into 72 tenths gives 72 ÷ 3 = 24. The other values would come from dividing by different numbers (for example, dividing by 0.9 gives 8, dividing by 3 gives 2.4, dividing by 0.06 gives 120), which isn’t the situation here.

Dividing by a decimal works best by removing the decimals first. If we multiply both numbers by the same power of 10, the value doesn’t change. Here, multiply top and bottom by 10: 7.2 × 10 = 72 and 0.3 × 10 = 3, so it becomes 72 ÷ 3. Since 72 divided by 3 is 24, the result is 24. Think of 7.2 as 72 tenths and 0.3 as 3 tenths; asking how many 3-tenths fit into 72 tenths gives 72 ÷ 3 = 24. The other values would come from dividing by different numbers (for example, dividing by 0.9 gives 8, dividing by 3 gives 2.4, dividing by 0.06 gives 120), which isn’t the situation here.