40/5= 8 8 is 1% of the total people, 1% x 100 = 100%
8 x 100 = 800 people
The answer to this question would be: The newspaper has Eight hundred readers.
Part = Percent x Whole
40 = 5% x 800
Do the equation above to make sure your correct( it is) and if it doesn't come back to 40 then your math is incorrect and you have the incorrect answer
Do that with all math that your trying to find the whole for, its a helpful thing.