You haven't provided the steps.
mathisfun.com/geometry/construct-linebisect.html
Here is a useful link to the correct steps. The instructions may not be exactly the same but I think you can do it.
Answer:
18
Step-by-step explanation:
Answer: 13300
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Work Shown:
A = event that it rains
B = event that it does not rain
P(A) = 0.30
P(B) = 1-P(A) = 1-0.30 = 0.70
Multiply the attendance figures with their corresponding probabilities
- if it rains, then 7000*P(A) = 7000*0.30 = 2100
- if it doesn't rain, then 16000*P(B) = 16000*0.70 = 11200
Add up the results: 2100+11200 = 13300
This is the expected value. This is basically the average based on the probabilities. The average is more tilted toward the higher end of the spectrum (closer to 16000 than it is to 7000) because there is a higher chance that it does not rain.
