18M.1.SL.TZ2.T_12
The histogram shows the time, t, in minutes, that it takes the customers of a restaurant to eat their lunch on one particular day. Each customer took less than 25 minutes.
The histogram is incomplete, and only shows data for 0 ≤ t < 20.
The mean time it took all customers to eat their lunch was estimated to be 12 minutes.
It was found that k customers took between 20 and 25 minutes to eat their lunch.
Write down the mid-interval value for 10 ≤ t < 15.
[1]
a.
Write down the total number of customers in terms of k.
[1]
b.i.
Markscheme / solution
* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.
12.5 (A1) (C1)
[1 mark]
a.
33 + k OR 10 + 8 + 5 + 10 + k (A1)
Note: Award (A1) for “number of customers = 33 + k”.
[1 mark]
b.i.
Examiners’ report
[N/A]
a.
[N/A]
b.i.