Answer:
53.57%
Step-by-step explanation:
We have to calculate first the specific number of events that interest us, if at least 3 are girls, they mean that 2 are boys, therefore we must find the combinations of 3 girls of 5 and 2 boys of 3, and multiply that, so :
# of ways to succeed = 5C3 * 3C2 = 5! / (3! * (5-3)!) * 3! / (2! * (3-2)!)
= 10 * 3 = 30
That is, there are 30 favorable cases, now we must calculate the total number of options, which would be the combination of 5 people from the group of 8.
# of random groups of 5 = 8C5 = 8! / (5! * (8-5)!) = 56
That is to say, in total there are 56 ways, the probability would be the quotient of these two numbers like this:
P (3 girls and 2 boys) = 30/56 = 0.5357
Which means that the probability is 53.57%
Answer:
90 customers
Step-by-step explanation:
Total shift time = 2 hours
1 hours = 60 minutes
Total shift time minutes = 2*60 minutes = 120 minutes
Average Time taken to serve 1 customer = 1 minute 20 seconds
lets convert 1 minute 20 seconds in fraction
60 seconds = 1 minute
20 seconds = 20/60 minutes = 1/3 minutes
Thus,
Average Time taken to serve 1 customer = 1 minute + 1/3 minutes = 4/3 minutes
Lets assume she served x customer in her 2 hour shift
total time taken to serve x customer =x*Average Time taken to serve 1 customer = 4x/3 minutes
Given that she the customers for her shift time which is 120 minutes
4x/3 minutes = 120 minutes
x = 120*3/4 = 90
Thus,
Kimiko served 90 customers and this is the number of customer which came through the drive thru during those 2 hours.
(-1)+(-6)= -7
-7 + 6 = -1
therefore, the answer is 6.
Answer:
Step-by-step explanation:
