Division with decimals

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Division when the divisor is larger than the dividend

Question 3

0.4 ÷ 0.5 = 4 ÷ 5 (Multiply the dividend and the divisor by 10)
= \(\dfrac{4}{5}\)    
= 0.8.    

Illustration

We start with a unit square.

a unit square and a rectangle of length 0.8 and width 0.5.

Detailed description of diagram


The diagram illustrates:

0.4 ÷ 0.5 = 0.8.
0.4 ÷ 0.8 = 0.5.
0.8 × 0.5 = 0.5 × 0.8 = 0.4.

Exercise

1Try these without a calculator:

a = check answer for question 1a
b = check answer for question 1b
c = check answer for question 1c
d = check answer for question 1d

2Illlustrate the following divisions using a strip of squares with each side of length 0.1
  (as used in Question 1 on page 2 Open in new window).
a 0.9 ÷ 0.3
b 1.5 ÷ 0.5

3Complete the following without a calculator.
a12.312 ÷ 3
b1.28 ÷ 0.4
c 6 ÷ 0.003
d 2.4 ÷ 0.08

Answers to exercise 2

a Diagram shows a strip 0.9 units long divided into sections of length 0.1. Three groups of length 0.3 are indicated.
b Diagram shows a strip 1.5 units long divided into sections of length 0.1. Three groups of length 0.5 are indicated.

Detailed description of video


Illustrating division

 

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