Question

Rob collects data about how many customers enter and leave a store every hour. He records a positive number for customers entering the store and a negative number for customers leaving the store each hour.
a. During which hour did more customers leave the most?

b. There were 75 customers in the store at 1:00. The store must be emptied of customers when it closes at 5:00. How many customers must leave the store between 4:00 and 5;00?

Entering Leaving
1:00 to 2:00 30 -12
2:00 to 3:00 14 -8
3:00 to 4:00 18 -30

Answer 1

To answer the question, we utilize the given data and solve for the number of customers left in the store after every 1 hour interval.

Initially, there were 75 customers.

1:00 to 2:00 :        75 + 30 - 12 = 93
2:00 to 3:00   :      93 + 14 - 8   = 99
3:00 to 4:00   :      99 + 18 - 30 = 87
4:00 to 5:00   :  If the store does not accept any more customers except those who are already inside then, all 87 must leave between 4:00 to 5:00 in order to empty out the store by 5:00

ANSWER: (a) 4:00 to 5:00
                 (b) 87 customers