Multiply Decimals Unit 5 Test Review

​James starts at 0.20 which is the first hash mark. He needs to move 4 more hash marks to show that he bought 5 airheads. The total cost should end up at $1.

​Because 10.4 = 10.40, my product does have two decimal place values but we do not always need to write the 0 in the hundredths place if there are no numbers to the right of it.

​Each color represents a number in the model. In this example the grey shows 5 full columns, which is equal to 0.50 (5 tenths or 50 hundredths). The pink is equal to 0.20 (2 tenths or 20 hundredths). Where they overlap, shows the product of 0.10 (1 tenth or 10 hundredths).

​1.15 x 1.6 =

(115 x 1/100) x (16 1/10)

​(115 x 16) x (1/100 x 1/10)

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​This opportunity is all about place value. The fractions tell us to move the decimal. The decimal place value in the product must equal the sum of the decimal place value in both factors.