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. 0.029·0.01
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 the product has $1 + 1=2$ 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 the product has $2+2 = 4$ 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 the product has $2 + 1=3$ decimal places.
$0.75\times0.2 = 0.15$

Answer:

(a) 0.72

2.