Answer:
x ≈ - 10.65, x ≈ - 5.35
Step-by-step explanation:
Given
(x + 8)² - 7 = 0 ( add 7 to both sides )
(x + 8)² = 7 ( take the square root of both sides )
x + 8 = ± ( subtract 8 from both sides )
x = - 8 ± , thus
x = - 8 - ≈ - 10.65
x = - 8 + ≈ - 5.35
Answer:
The expected winnings for a person buying 1 ticket is -0.2.
Step-by-step explanation:
Given : A raffle offers a first prize of $1000, 2 second prizes of $300, and 20 third prizes of $10 each. If 20000 tickets are sold at 25 cents each, find the expected winnings for a person buying 1 ticket.
To find : What are the expected winnings?
Solution :
There are one first prize, 2 second prize and 20 third prizes.
Probability of getting first prize is
Probability of getting second prize is
Probability of getting third prize is
A raffle offers a first prize of $1000, 2 second prizes of $300, and 20 third prizes of $10 each.
So, The value of prizes is
If 20000 tickets are sold at 25 cents each i.e. $0.25.
Remaining tickets = 20000-1-2-20=19977
Probability of getting remaining tickets is
The expected value is
Therefore, The expected winnings for a person buying 1 ticket is -0.2.