Answer:
3
Step-by-step explanation:
Answer : A
The word "increased" indicates a plus sign. The word "is equal" helps show us show that something is = to 15
Multiply is product. Divide is quotient
You need to do 20 divide by 21 to get a decimal. Then if you multiply the decimal by hundred you should get the percentage.
Attached is a screenshot of spreadsheet used to do this problem.
You will see the excel functions used for each column. The average score is highlighted in blue.