Answer:
Expected number of people in concert = 7900 people
Step-by-step explanation:
We have given,
In an concert,
if it's not raining , number of people will attend concert = 17000 people
If it's raining , then number of people will attend concert = 4000 people
Since, probability of raining = 70% = 0.7
Then probability of not raining = 30% = 0.3
So,
Expected number of people in concert = 0.3 * 17000 + 0.7 * 4000
Expected number of people in concert = 5100 + 2800
Expected number of people in concert = 7900 people