Question

Explain how using
basic facts can help you find 10 x 20 x 30 x 40 mentally.
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Answer 1

Explanation:

We know that 1x 2 is 2 (add the 2 zeros to make it 200)

And 3x4 is 12 (add 2 zeros and make it 1200) Then Add

Answer 2

Answer: 240000

Step-by-step explanation: 10 · 10 · 10 · 10 = 10000

1 · 2 · 3 · 4 = 24

10 · 20 · 30 · 40 = 240000