Question

activity 1
multiply the decimal numbers together. choose the correct answer.

1. 0.8·0.9

(a) 0.72
(b) 0.072
(c) 7.2

1. 0.02·0.25

(a) 0.50
(b) 0.0050
(c) 0.050

1. 0.75·0.2

(a) 0.15
(b) 0.015
(c) 1.50

1. 0.5·4.8

(a) 0.024
(b) 0.24
(c) 2.40
activity 2
multiply using the traditional method. check your work using rounding

1. 0.75·0.8
2. 0.029·0.1
3. 0.54·0.7
4. 0.25·0.4
5. 0.1·0.08
6. 2.5·0.5

activity 3
circle the graphs that show indirect relationships.
graph a
graph b
graph c
graph d

Explanation:

Activity 1

1.

Step1: Multiply as whole - numbers

$8\times9 = 72$

Step2: Count decimal places

$0.8$ has 1 decimal place and $0.9$ has 1 decimal place, so total 2 decimal places.
$0.8\times0.9=0.72$

Step1: Multiply as whole - numbers

$2\times25 = 50$

Step2: Count decimal places

$0.02$ has 2 decimal places and $0.25$ has 2 decimal places, so total 4 decimal places.
$0.02\times0.25 = 0.0050$

Step1: Multiply as whole - numbers

$75\times2=150$

Step2: Count decimal places

$0.75$ has 2 decimal places and $0.2$ has 1 decimal place, so total 3 decimal places.
$0.75\times0.2 = 0.15$

Answer:

(a) 0.72

2.