Multiplying Numbers with DecimalsDate: 12/7/95 at 19:34:41 From: Anonymous Subject: decimals What is 9.4 x 9.6? Date: 12/23/95 at 22:49:2 From: Doctor Elise Subject: Re: decimals Hi! Okay, this is the way you multiply decimals without a calculator: Basically, it's the same as multiplying whole numbers, with a twist! If you had 94 x 96, you'd do it like this: 94 x 96 ____ 564 (this is 6 times 94) 8460 (this is 9 times 94 times 10) ______ 9024 (564 + 8460, which is the answer) Now, if we have decimals, we count how many numbers there are to the right of the decimal point, like this: in 9.4, the 4 is to the right of the decimal point so that's one, and in 9.6 the 6 is to the right of the decimal point, so that's another, for a total of 2. Then we put the decimal point in the answer 2 places to the left of the 'ones' column, like this: 90.24. If you think about it, you know that 9x9 = 81, and 10x10 = 100, so 9.4 x 9.6 has to be between 81 and 100! Does this help? -Doctor Elise, The Geometry Forum |
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