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Basic Math/1.5 multiplied by -1

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Question
I know that 1 and a half multiplied by -1 equals .5, or 1/2, but I cannot figure out why. Why isn't it -1/2? There's 1 1/2 multiplied by a negative. Why isn't it negative 1/2? I have to take the GRE and math has always been my worst subject, but I thought I knew that multiplying a positive by a negative was always going to be a negative. Why not in this case? Can you help?

Answer
Hello, Carrie.

Any number multiplied by 1 will give you that same number for an answer (44 x 1 = 44). Any number multiplied by -1 will give you the same number, with the opposite sign (5 x -1 = -5; -2 x -1 = 2).

I don't know how you came up with 1.5 x -1 equaling 1/2. 1.5 x -1 equals -1.5.

Multiplying a positive number by a negative number always yields a negative answer.

I hope this helps.

Regards,
John

Basic Math

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John Zalewski

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I can help you solve problems involving fractions, decimals, ratios, and algebra. I can teach you how to do math faster, and even in your head. I can teach math definitions, and help you study, if necessary. Please do not ask any graphing, trigonometry, or calculus questions. Try to work through homework questions before asking for assistance.

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