Use the table given to answer questions (a) and (b).
- What was the total number of wafers sold?
- Express your answer in terms of z in the simplest form. If z = 30, how many more wafers were sold on Sunday than on Saturday?
Day | Number of wafers sold |
Monday to Friday | 3z per day |
Saturday | z + 21 |
Sunday | 4z - 5 |