wireless keyboard sold = x
regular keyboard sold = 3x
105x + 84(3x) = 4998
105x + 252x = 4998
357x - 4998
x = 14 <============ Number of wireless keyboard
3x = 3(14) = 42 <============ Number of regular keyboard
Answer:
0.04865 or 4.9%
Step-by-step explanation:
This is a binomial distribution function which is expressed as:
Where:
- p=probability of success
- x=number of successful events
- n=size of the sample
Given that p=0.03, n=12 and x=2+, the probability of a cash back is calculated as:
Hence, the probability of a cash return is 0.04865 or 4.9%
6,256 is the answer to the question.
The answer is 9...............................