Multiplying decimals is multiplying you already know how to do. The only new question is where the point goes.
Not started yet.
By the end of this lesson your student should be able to multiply two decimals and place the decimal point correctly, either by estimating or by counting the decimal places in the factors.
🚨 Lining up the decimal points, the way you do for addition. Multiplication doesn't line them up; you multiply as whole numbers and place the point at the end.
Counting places from the wrong end. Count from the right of the product, and add zeros on the left if you run out of digits, as in 0.005 x 0.5 = 0.0025.
Draw a 10-by-10 grid, shade 4 columns one way and 6 rows the other, and count the overlap: 24 small squares out of 100, so 0.24. That picture is the reason the counting rule works, and it's worth doing once by hand.
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Before You Start
The words this lesson uses. Tap a card to see what it means, then come back to them whenever a question uses one.
Part One
Questions about the story you just read. Pick your answer straight off, or press Find it in the story if you would rather hunt for the sentence first.
Part Two
The word cards are at the top of this page. Look back at them as often as you need, then answer.