Answer:
- same: 30×40 = 1200
- different: 20×50 = 1000
Step-by-step explanation:
Same: 30×40 = 1200 . . . . . 2 zeros in the factors; 2 in the product
Different: 20×50 = 1000 . . . 2 zeros in the factors; 3 in the product
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Same: 0.3×0.4 = 0.12 . . . . no zeros in the factors; no zeros in the product
Different: 0.2×0.4 = 0.08 . . . no zeros in the factors; 1 zero in the product after the decimal point
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For a product, the number of zeros will be different if the combined factors of the numbers increase the number of factors of 10 beyond the sum of the factors of 10 of the numbers being multiplied.
<u>Example</u>: neither 2 nor 5 has a factor of 10, but their product does.
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For a product that is a decimal fraction, the number of leading zeros will increase if the product of the mantissas of the numbers is less than 10. The number of trailing zeros will increase under the conditions discussed above. (0.25×0.4 = 0.100)
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<em>Additional comment</em>
Here, the term "mantissa" is used to refer to the portion of the number written in scientific notation that multiplies the power of 10.
