math - Hollice, Tuesday, October 2, 2007 at 5:10pm
80 is 40% of what number
Here are a couple of ways of solving your problem.
Proportion:
40/100 as 80/x
x = ?
Or algebraically:
.4x = 80
x = 80/.4
x = ?
To find out what number 80 is 40% of, we can use the formula for finding a percentage of a number. The formula is:
(Percentage x Number) / 100 = Result
In this case, we know that 80 is 40% of a number, so we have:
(40 x Number) / 100 = 80
To solve this equation and find the value of the unknown number, we can cross-multiply:
40 x Number = 80 x 100
Simplifying the right side of the equation:
40 x Number = 8000
Now, we can solve for the unknown number by dividing both sides of the equation by 40:
Number = 8000 / 40
Number = 200
Therefore, 80 is 40% of 200.