3.4 Multiplying Decimals

Focus: Multiply decimals using paper and pencil and Base-10-Blocks.

Blocks that are used are:

On your graph paper, draw blocks to model the number 2.53

Example: Multiply 1.3 by 2.1
Estimate first, then calculate using Paper & Pencil

Steps to follow:

1.) Multiply as if they were whole numbers.
2.) Count the number of digits after the decimal in the question.
There should be the same number of digits after the decimal in your answer.

Example 2 - Multiply 0.7 x 2.3

No Flats = 0.00
14 Rods = 1.40
21 units =

add ... =



Practice: In groups of 3-4, use your blocks and graph paper to complete the following questions:

1.2 x 0.3 = 3.2 x 1.4 =
2.1 x 1.2 = 4.1 x 0.2 =

2.0 x 0.8 = 3.4 x 1.6 =


Homework - pg. 102-103 #1-12 (odd)