Answer:
Step-by-step explanation:
Observe in the figure given in the exercise that four right triangles are formed.
In this case you can use the following Trigonometric Identity to solve this exercise:
From the figure you can identify that:
Then, you can substitute values:
The next step is to solve for DE in order to find its value. This is:
Finally, rounding the result to the nearest tenth, you get that this is:
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.