Question

last weekend, 8 servers worked at a local restaurant. the table below gives information about the number of customers served at lunch and dinner.

server	lunch	dinner
bob	55	74
juan	43	69
yoko	32	49
chau	31	44
lucy	22	39
maya	18	36
trey	13	34

(a) give the set of servers who served more than 30 customers at lunch. use roster form for your set.
(b) give the set of servers who served more than 60 customers at dinner. use roster form for your set.

Explanation:

Step1: Check lunch - customer numbers

Check the lunch - customer numbers for each server in the table and select those greater than 30.
Ann has 56, Bob has 55, Juan has 43, Yoko has 32, Chau has 31.

Step2: Write set for (a)

The set of servers who served more than 30 customers at lunch is $\{\text{Ann}, \text{Bob}, \text{Juan}, \text{Yoko}, \text{Chau}\}$.

Step3: Check dinner - customer numbers

Check the dinner - customer numbers for each server in the table and select those greater than 60.
Ann has 82, Bob has 74, Juan has 69.

Step4: Write set for (b)

The set of servers who served more than 60 customers at dinner is $\{\text{Ann}, \text{Bob}, \text{Juan}\}$.

Answer:

(a) $\{\text{Ann}, \text{Bob}, \text{Juan}, \text{Yoko}, \text{Chau}\}$
(b) $\{\text{Ann}, \text{Bob}, \text{Juan}\}$