[Question]: At a convention, 16 of 36 delegates arrived with pre-printed name badges. Half of the remaining delegates made their own, hand-written name badges. How many delegates were not wearing name badges?
[Answer]: There were 36 - 16 = 20 without pre - printed name badges. Then 20 / 2 = 10 made hand - written badges. There were 20 - 10 = 10 with no name badge.
So the answer is 10.

[Question]: Rob planned on spending three hours reading in preparation for his literature exam. If he ends up spending only three-quarters of this time reading, and he reads a page every fifteen minutes, how many pages did he read in this time?
[Answer]: 1 hour is 60 minutes so 3 hours is 3 * 60 = 180 minutes. Three - quarters of 180 minutes is (3 / 4) * 180 = 135 minutes. He spends 15 minutes on 1 page so he will spend 135 minutes on 135 / 15 = 9 pages.
So the answer is 9.

[Question]: Since the 40th president launched his reelection campaign today, he has raised $10,000 in campaign funds. His friends raised 40% of this amount and his family raised 30% of the remaining amount. The rest of the funds are from his own savings for the election. How much did he save for the presidency?
[Answer]:
The total amount of money raised from friends contribution is 40 / 100 * $10000 = $4000. Minus his friend's contribution, the 40th president has raised $10000 - $4000 = $6000. The family raised 30 / 100 * $6000 = $1800. If the family raised $1800, the savings the 40th president had for the campaign is $6000 - $1800 = $4200.
So the answer is 4200.