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If 10% of a number is 36 and 55% of the same number is 198, find 45% of that number.

1 Answer

8 votes

9514 1404 393

Answer:

162

Explanation:

There are many ways to work this. Perhaps the simplest is to recognize that 45% of the number is the difference between 55% of it and 10% of it.

0.55n -0.10n = 0.45n

198 -36 = 0.45n = 162

45% of the number is 162.

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If you like, you can find the number as ...

0.10n = 36

n = 36/0.10 = 360

Then you can verify (if you like), that 55% of it is 198:

0.55(360) = 198 . . . . true

Finally, you can figure 45% of it:

0.45(360) = 162

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Using proportions, you can determine the number to be ...

36/0.10 = n/0.45

n = 0.45(36/0.10) = 4.5(36) = 162

User Davies Odu
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