Cross Multiply
[tex] \frac{7}{x} [/tex] = [tex] \frac{28}{100} [/tex]
28x = 100 · 7
28x = 700
28 28
x = 25
or you can set it up like this...
28% of what number is 7
1. Change 28% to .28
.28 of what number is 7
2. Of means multiply
.28 · what number is 7
3. what number is going to be a variable I will use x
.28 · x is 7
4. is means equal to
.28 · x = 7
Finally you can solve the equation
.28 · x = 7
divide both sides by .28
.28 · x = 7
.28 .28
x = 25
