21 is 75% of what number?

The easiest way for me is to remember is means an equal sign and of means multiplication.

21 =.75 * n First you want to multiply. 75 by n. To get. 75n

21 =.75n Next you are going to divide both by. 75. Which is 28 and n

Now the final answer is n=28

21 is 75% of 28.

The way I did it was to just divide 21:3 (the 75%), which I know will evenly divide into 7, and added 7 (the missing 25%), to get my answer of 28.

You can go back and check your work in that 100 : 4 = 5, and 28 : 4 = 7. Not sure if that's how your teacher wants you to work it but that's the correct answer.