Answer:
3.4 minutes
Step-by-step explanation:
Every morning there are expected 240 customers who arrive at bank for the customer service. There are on average 240 customers arriving to the bank every morning. There are total 5 bank tellers and they take average 3 minutes to help customer. The average time each bank teller spends on satisfying a customer will be calculated using the linear model,
Using wait time calculator:
Average service time / standard deviation
Ce = 3/1.5 = 2
The spent time on a customer is 3.4 minutes.
Since the slope is rise/run, 1/6 goes up one, right 6. Perpendicular is opposite that. so a slope of -6 goes down 6 and right 1. (as a fraction it's -6/1)
So if 6 out of 40 are incorrect, 40-6= 36 must be correct.
In order to gain percentage you do proportions.
36/40 = x/100.
Multiply 36 times 100 then divide by 40, which is 90.
The answer is 90%.
90% of the questions he got were correct.