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Can anyone show me how to multiply $-.05$ times $-.04$ by hand please?

I do it by hand and I get $.20$ but my book says the correct result is $.002$.

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    $5/100$ times $4/100$ is $20/10000=2/1000$2012-03-18
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    what would be answer if you multiply .05 and .04?2012-03-18
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    $(-.05)(-.04)={-5\over 100}\cdot{-4\over100}={20\over 10000}=-.002$.2012-03-18
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    If we leave out the decimals points and signs, we are left with $5 \times 4 = 20.$ Now we fix the signs: $- \times - = +.$ Good. Next we fix the decimal point: $2 + 2 = 4$ decimal points. So fit $20$ in 4 digits, that's $20 = 0020.$ Now count 4 digits from the right and put the decimal point. That's $0.0020.$2012-03-18
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    @David: $+.002$2012-03-18
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    Example $1.2 \times -0.5.$ First, $12 \times 5 = 60.$ The decimal places: $1$ (from $1.2$) $+ 1$ (from $0.5$) $= 2.$ So *put the decimal point after 2 digits from the right.* That's $0.60.$ Next fix the signs: $+ \times - = -.$ So the result is $-0.60.$2012-03-18
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    Anyone else find it sad people don't know how to multiply decimals without a calculator?2012-03-19

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