Solution:

Multiplication calculation is checked by division, for example:

15x 16=240

Check calculation:

240÷ 16= 15

Or: 240÷ 15= 16

So the multiplication calculation is correct.

Extended data:

3×5 means the addition of five 3s.

5x3 represents the addition of three 5s.

In the above multiplication, the factor after the multiplication sign is often taken as the multiple of the factor before the multiplication sign.

Ⅰ? Multiplication principle: If the dependent variable f is in direct proportion to the independent variable X 1, X2, X3...Xn, and each independent variable is qualitatively different, if any independent variable f is missing, it will lose its meaning, which is called multiplication.

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