Grade 4 - Progress in Mathematics

Find the Mean

5-16

Aidan scored 75, 85, 90, 80, and

90 on math tests last term. What

was his mean, or average, test score?

To find the mean:

Add the Divide the sum by the

numbers. number of addends.

75 84 mean

85 5 
 4  2  0 

90 
 40

80 20

 90 
 20

420

Aidan’s mean test score was 84.

Study this example.

Find the mean: $ 2.44, $ 3.68, $ 4.20, $ 1.64

$ 2.44 $ 2.99 mean

3.68 4 
$ 11 .9 6 

4.20 
 8

 1.64 39

$ 11.96 
 36

36


 36

Think

5 addends

Think

4 addends

Find the mean.

1. 36, 42, 72 2. 256, 498 3. 93, 126, 117


2. 500, 250 5. 49, 93, 86 6. 88, 0, 78, 90

3.4

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