Percentages are ratios of an amount compared to 100. The percent change of an old to new value is equal to 100% x \({ new - old \over old }\).
Monica scored 90% on her final exam. If each question was worth 4 points and there were 320 possible points on the exam, how many questions did Monica answer correctly?
| 83 | |
| 72 | |
| 64 | |
| 68 |