Question

a) how many total days were included in the sample?n =
b) how days had between 180 and 200 customers?number of days =
c) how many days had between 120 and 180 customers?number of days =
d) how many days had less than 200 customers?number of days =

Explanation:

Step1: Calculate total days (a)

Add all frequencies: \(1 + 2+3 + 3+6 + 7+3=25\)

Step2: Find days between 180 - 200 (b)

Read frequency for \(180 - 200\) interval: \(6\)

Step3: Find days between 120 - 180 (c)

Sum frequencies for \(120 - 140\), \(140 - 160\), \(160 - 180\): \(2 + 3+4 = 9\)

Step4: Find days less than 200 (d)

Sum frequencies for intervals \(100 - 120\), \(120 - 140\), \(140 - 160\), \(160 - 180\), \(180 - 200\): \(1+2 + 3+3+10=19\)

Answer:

a) \(n = 25\)
b) \(6\)
c) \(9\)
d) \(19\)