Final answer:
The expectation if a person buys four tickets is $5.20.
Step-by-step explanation:
To find the expectation if a person buys four tickets, we need to calculate the expected value of the winnings.
The probability of winning each prize is as follows:
$1000 prize = 1/1000,
$500 prize = 2/1000,
$300 prize = 3/1000, and
$200 prize = 4/1000.
The expected value is calculated by multiplying the probability of winning each prize by the value of that prize, and then summing all of these values.
For example: (1/1000) * $1000 + (2/1000) * $500 + (3/1000) * $300 + (4/1000) * $200 = $5.20
So, the expectation if a person buys four tickets is $5.20.