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18 is 45% of what ?

Answer 1

Eva Abramson

#40#

#18/40# will give you #0.45#, which is equal to #45%#.

How to solve it:

#" "18 = 0.45x#

#" "18/0.45 = x#

#" "40 = x#

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Answer 2

Kennedy Adams

#40#

The proportion I like to use with these types of problems goes like:

#"percent"/100 = "part"/"whole"#

Part/whole can also be written as "is/of"

So in this case:

Now:

#45/100 = 18/x#

We can cross multiply to get:

#45x = 1800#

#x = 40#

Hope this helps!

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Answer 3

Abigail Allen

#18# is #45%# of #40#.

Let #x# represent the unknown number.

#45%=45/100=0.45#

#0.45x=18#

Divide both sides by #0.45#.

#x=18/(0.45)#

#x=40#

Check.

#0.45(40)=18#

#18# is #45%# of #40#.

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Answer 4

Eva Adamson

To find what number 18 is 45% of, divide 18 by 0.45. The result is 40.

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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.