[Question]: John buys a box of 40 light bulbs. He uses 16 of them and then gives half of what is left to a friend. How many does he have left?
[Answer]: He had 40 - 16 = 24 left after using some. Then after giving some away he is left with 24 / 2 = 12.
So the answer is 12.

[Question]: A convenience store sold 100 bags of chips in a month. In the first week, 15 bags of chips were sold. In the second week, thrice as many bags of chips were sold. There was an equal number of chips sold in the third and fourth week. How many chips was each sold in the third and fourth week?
[Answer]: In the second week, 15 x 3 = 45 bags of chips were sold. So there was a total of 45 + 15 = 60 bags of chips sold on the first and second week. Thus, a total of 100 - 60 = 40 bags of chips were sold on the third and fourth week. Therefore, 40 / 2 = 20 bags of chips were each sold on the third and fourth week.
So the answer is 20.

[Question]: Dawn earns 48,000 a year in 12 equal monthly payments. Each month, she saves 10% of her salary. How much does she save each month?
[Answer]:
Dawn earns $4,000 a month because 48,000 / 12 = 4000. She saves $400 a month because 4,000 x .1 = 400.
So the answer is 400.