Percentages in AlgebraDate: 12/29/95 at 0:55:34 From: Christine M Moss Subject: Simple algebra What number increased by 30% = 260? I know the answer, but how did I get it? Thank you. Date: 1/3/96 at 17:0:0 From: Doctor Elise Subject: Re: Simple algebra Hi! Increasing a number by 30% is the same as adding 30% of the number to 100% of the number. If we call the number 'y', then the actual math problem becomes: 100% of y plus 30% of y = 260 In math problems, 'of' means multiplication, and percentages have to be converted into decimals, so we have (1.00 * y) + (.30 * y) = 260 (1.00 + .30) * y = 260 1.30 * y = 260 y = 260/1.3 Does this help? -Doctor Elise, The Math Forum |
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