multiply by

multiply by (something)

1. To use multiplication according to a particular factor. Finally, we have to multiply by seven to find the solution. If you multiply by 0.33, you'll get the portion of your rent that you are allowed to write off as a business expense.
2. To use multiplication on a given number according to a particular factor. In this usage, a noun or pronoun is used between "multiply" and "by." Multiply that number by 10—that's how much you owe me now! If you multiply nine by any single digit, the product will always be two digits that, when added together, equal nine!
See also: by, multiply
Farlex Dictionary of Idioms. © 2015 Farlex, Inc, all rights reserved.

multiply something by something

to use the arithmetic process of multiplication to expand numerically a particular number a certain number of times. Multiply the number of dependents you are claiming by one thousand dollars. Multiply 12 by 16 and tell me what you get.
See also: by, multiply

multiply by something

to use the arithmetic process of multiplication to expand numerically a certain number of times. To get the amount of your taxes, multiply by .025. Can you multiply by sixteens?
See also: by, multiply
McGraw-Hill Dictionary of American Idioms and Phrasal Verbs. © 2002 by The McGraw-Hill Companies, Inc.
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References in periodicals archive ?
Let me recap: multiply your shoe size by five, add 50, multiply by 20, add 1012 and subtract the year you were born.
Then subtract the amount of new policies Cameron's got and multiply by the amount of talented MPs he's got to carry them through.
It teaches you how to multiply by using skip counting.
Of course, if you want to be exact, you can find your target heart rate by using the standard formula where you subtract your age from 220 for men or 226 for women and multiply by 70 percent.
So I need to multiply by, I need the three I started with.
With a major port, Honduras is the country that can see its trade multiply by a large factor during the coming years.
Multiply length by width by depth in feet and divide by 1.25 or multiply by 8 and leave off the last right-hand digit.
Amoebas multiply by splitting--no one has observed sex--so clone mates with the same A-factor accumulate.