Percentages are ratios of an amount compared to 100. The percent change of an old to new value is equal to 100% x \({ new - old \over old }\).
Diane scored 80% on her final exam. If each question was worth 2 points and there were 200 possible points on the exam, how many questions did Diane answer correctly?
| 91 | |
| 78 | |
| 80 | |
| 70 |