Question

Tito wrote the following on the board. What is the unknown number?

50x80=50x(8x10)
=(50x8)x10
=?x10
=4000

Answer 1

400

Explanation:

It's because 50 times 8 is 400.

Also, it has to be 400 because the only number multiplied by 10 that gives 4000 is 400.

Answer 2

400
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