SOLUTION: When a number is decreased by 20% of itself, the result is 20. What is the number?

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Question 558896: When a number is decreased by 20% of itself, the result is 20. What is the number?
Answer by Theo(13342) About Me  (Show Source):
You can put this solution on YOUR website!
x equals the number.
x - .2 * x = 20
combine like terms to get:
.8 * x = 20
divide both sides of this equation by .8 to get:
x = 20 / .8
simplify to get:
x = 25
confirm by substituting in the original equation.
25 - .2 * 25 = 20
25 - 5 = 20
20 = 20
x is confirmed to be good.
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decimal equivalent for 20% is 20% divided by 100% = .2
x - .2 * x is equivalent to x * (1 - .2) which becomes x * .8 which is the same as .8 * x.