Question

A raffle has a grand prize of a European cruise valued at $12000 with a second prize of a weekend in San Diego valued at $500. If each ticket costs $3 and 10800 tickets are sold, what are the expected winnings far a ticket buyer? Express to at least three decimal place accuracy in dollar form (as opposed to cents).
Answer: $

Answer 1

(12000-3)*(probability of winning first prize) + (500-3)*(probability of winning second prize) + (-3)*(probability of not winning anything)

Answer 2

still there?

Answer 3

yeah

Answer 4

were you able to find an answer?

Answer 5

im caluclating it right now

Answer 6

ok, there are 10800 tickets

so the probability of getting first prize is 1/10800
the probability of getting second prize is 1/10800
and the probability of not winning anything is 10798/10800, understood?

Answer 7

yeah

Answer 8

great, you have everything you need, so plug everything into the formula and let me know what you get ~~~

Answer 9

i got -1.84259259 as the answer

Answer 10

@Vocaloid

Answer 11

can it be a negative?

Answer 12

good! you can round that to -1.84 since we're dealing with money

Answer 13

and yes! it can be negative

Answer 14

ah okay

Answer 15

a negative expected value means that, on average, we would expect to lose money after buying a ticket (since the probability of winning is so small!)

Answer 16

-1.84 didnt work

Answer 17

oh wait it says 3 decimal places

Answer 18

at least 3

Answer 19

oh whoops, I didn't read that part ;_; sorry

Answer 20

so should i just put in the whole decimal?

Answer 21

sure, if you'd like

Answer 22

it worked :D

Answer 23

thanks :D

Answer 24

whew, that's good, I thought I messed up somewhere