68 of the 400 students take AP Chemistry. To find how many don't, subtract the total from the ones that do.
![400 - 68 = 332](https://img.qammunity.org/2019/formulas/mathematics/middle-school/8qsq4xuu0bqcx5lb9rmjz8tdrs1r7bzkvs.png)
332 of the students don't take AP Chemistry. Divide 332 by 400 to get the decimal so that you can change it to a percent.
![332 / 400 = 0.83](https://img.qammunity.org/2019/formulas/mathematics/middle-school/mujp519c22d5aramhacqr68c4baecfl4d2.png)
To change a decimal to a fraction, move the decimal point 2 places to the right and add a percent sign.
![0.83 \rightarrow 83 \%](https://img.qammunity.org/2019/formulas/mathematics/middle-school/tr3a5i3sws4com7svs53wally8qbrlmnmr.png)
83% of the students don't take AP Chemistry