[Question]: Danny brings 3 watermelons to his family picnic. He cuts each watermelon into 10 slices. His sister brings 1 watermelon to the family picnic, and she cuts the watermelon into 15 slices. How many watermelon slices are there in total at the picnic?
[Answer]: From Danny, there are 3 * 10 = 30 watermelon slices. From his sister, there are 1 * 15 = 15 watermelon slices. There are a total of 30 + 15 = 45 watermelon slices.
So the answer is 45.

[Question]: A wheel on a certain machine makes 6 turns every 30 seconds. How many turns does it make in two hours?
[Answer]: Since there are 60 seconds in 1 minute, then there are 60 / 30 = 2 sets of 30 seconds in a minute. So a wheel makes 6 x 2 = 12 turns in 1 minute. Since there are 60 minutes in 1 hour, then a wheel makes 12 x 60 = 720 turns in an hour. Therefore, the wheel makes 720 x 2 = 1440 turns in 2 hours.
So the answer is 1440.

[Question]: Tommy has 3 toy cars. His neighbor, Jessie, has 3 cars too. Jessie's older brother has 5 more cars than Tommy and Jessie. How many cars do the three of them have altogether?
[Answer]:
Tommy and Jessie have 3 + 3 = 6 cars. Jessie's brother has 5 + 6 = 11 cars. Altogether, they have 6 + 11 = 17 cars.
So the answer is 17.