Thomas calculates 9×7 by thinking avout it as 70-7=63. Explain thomas' strategy.

2 answers:

6 0

Thomas uses the distributive property

9 X 7 = (10 X 7) - (1 X 7)
= 70 - 7
= 63

9 groups of 7 is equal to 10 groups of 7 subtract 1 group of 7.

madam [21]4 years ago

4 0

10 x 7 = 70
1 x 7 = 7
9 x 7 = 70 - 7
9 x 7 = 63

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