Let’s try 32 × 4. We can make an estimate first. 32 rounds down to 30, so 30 × 4 = 120 because 3 tens × 4 = 12 tens.
2
Look at the two different methods used to solve 32 × 4. What is the same and what is different about them? 32 × 4 = 30 × 4 = 120 2 × 4 = 8 120 + 8 = 128
H T 3
O 2 4
×
10 10 10 10 10 10 10 10 10 10 10 10
1 1 1 1 1 1 1 1
2 ones multiplied by 4 and then 3 tens multiplied by 4
1 2 8
128 is a little more than the estimate of 120.
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04/05/2022 15:50
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