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If 9% of a number is 18, what is the number?

Answer 1

Eva Adamson

The number is #200#

Let the number be #x#

#9# percent of the number means #color(white)("XXX")9/100 xx x#

So if #18# is #9# percent of the number: #color(white)("XXXXXXXXXX")18=color(white)("XXXX")9/100 xx x#

#color(white)("XXX")rarr 100/9 xx 18 = 100/9 xx 9/100 xx x#

#color(white)("XXX")rarr 100/cancel(9) xx cancel(18)^2 = cancel(100)/cancel(9) xx cancel(9)/cancel(100) xx x#

#color(white)("XXX")rarrcolor(white)("XXXXX")200 = color(white)("XXXXXXXXX")x#

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Answer 2

Kennedy Adams

To find the number, divide 18 by 9% (which is 0.09). The result is 200.

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Answer from HIX Tutor

When evaluating a one-sided limit, you need to be careful when a quantity is approaching zero since its sign is different depending on which way it is approaching zero from. Let us look at some examples.