Use the table given to answer questions (a) and (b).
- What was the total number of puffs sold?
- Express your answer in terms of a in the simplest form. If a = 20, how many less puffs were sold on Saturday than on Sunday?
Day | Number of puffs sold |
Monday to Friday | 4a per day |
Saturday | a + 20 |
Sunday | 4a - 7 |