Answer: 18 tickets.
Step-by-step explanation:
If we compute:
1282/65 = 19.723
So we have enough for 19 prices, and 0.723 for the next one.
Then we must find the next multiple of 65, near 1282.
Now, the easier way to solve this will be:
To have enough for 20 prices, Carrie needs to have at least 20 times 65 tickets.
So she needs:
20*65 = 1300 tickets.
And she has 1282 tickets.
Then the number of tickets that she needs is:
1300 - 1282 = 18 tickets.
She needs 18 more tickets to have enough for the 20th prize.