4.6: Dividing decimals

To divide two decimal numbers, create an equivalent division problem by multiplying the dividend and the divisor by the same product of 10s so that the divisor becomes a whole number. For example,

• 1.242 ÷ 0.27
• = (1.242 x 100) ÷ (0.27 x 100)    [multiply dividend and divisor by the same product of 10s, 100 in this case]
• = 124.2 ÷ 27
• = 4.6    [use 4.1: Dividing integers to calculate 124.2 ÷ 27]
• This works because we’ve multiplied and divided by the same product of 10s, which creates an equivalent problem with the same answer.

Here are two more examples:

• 91 ÷ 2.6
• = (91 x 10) ÷ (2.6 x 10)    [multiply dividend and divisor by 10]
• = 910 ÷ 26
• = 35

• 159.1 ÷ 0.43
• = (159.1 x 100) ÷ (0.43 x 100)    [multiply dividend and divisor by 100]
• = 15910 ÷ 43
• = 370

The video below works through some examples of dividing decimals.