Grade 4 - Progress in Mathematics

Multiply Money

4-8

Walkie-Talkies $8.59 each

Periscopes $4.58 each

Magnifying Glasses $7.50 each

Decoder Rings $ .99 each

Invisible Ink Markers $1.56 each

Notebooks $3.39 each

Cesar buys 8 notebooks for

the Detective Club. Each

notebook costs $ 3.39.

What is the total cost?

To find the total cost,

multiply: 8 
$ 3.39

First, estimate using $ 3 .39

front-end digits: 
 8

about $ 24. 00

Then multiply.

To multiply money:


Multiply the same way you multiply whole numbers.


Write a decimal point in the

product two places from the right.


Write the dollar sign.

The total cost is $ 27.12.

Study these examples.

1 2

$.6 4 $2.0 7


 3 
 4

$1.9 2 $8.2 8

Use front-end digits to estimate. Then multiply.

1. $ .46 2. $ .38 3. $ .52 4. $ .74 5. $ .25
   
   6
   8
   7
   9
   3


2. $ 1.05 7. $ 5.73 8. $ 6.26 9. $ 8.30 10. $ 4.52
   
   2
   5
   4
   7
   9

Think

$27.12 is close to $24.00.

The answer is reasonable.

3 7

$3.3 9


 8

$2 7.1 2

3.2

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