4.9 ÷ 7
= (4.9 x 10) ÷ (7 x 10)
= 49 ÷ 70
= 0.7
Think of 49 ÷ 7 = 7. Since it is 4.9, instead of 49, then the answer would be 0.7, instead of 7.
To represent this in base ten blocks, you can try a few things. One option is to use a flat, 100-block, which represents 100 small squares. You could think of the whole block as one whole, and you could take 7 rows from it, representing 70/100, or 7/10 (0.7).
Another way you could do is take a 10-block rod, and take 7 individual squares from it, to represent 7/10, or 0.7.
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