Question

Find the number if:

5/9 of it is 90.

And another similar question;

Find the number if:

7/3 of it is 5 5/6


I need help with both of these questions.

Answer 1

162

Explanation:

If it is 5/9 of the original number is 90 we can just divide 90 by 5 to find 1/9 and then we can multiply that with 9 to get 9/9 which is the whole number.

90 ÷ 5 = 18

18 × 9 = 162

Answer 2

162 and
`(5)/(2)`

Explanation:

To find the original number multiply by the reciprocal of the multiplier, that is

90 ×
`(9)/(5)` =
`(810)/(5)` = 162

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Similarly

Change the mixed number into an improper fraction

5
`(5)/(6)` =
`(35)/(6)` , then

`(35)/(6)` ×
`(3)/(7)` ( cancel 35 and 7 by 7 / cancel 6 and 3 by 3 )

=
`(5)/(2)` ×
`(1)/(1)`

=
`(5)/(2)`