[Question]Paul is working at a university. He is part of a big project, which involves 70 scientists in total. Half of them are from Europe and one-fifth are from Canada. The rest are from the USA. How many scientists in this project are from the USA?
[Answer]Of all the scientists taking part in the project, half of them are from Europe, which means 70 * 0.5 = 35 people. The number of researchers from Canada is 70 * 1 / 5 = 14 people. That means there are 70 - 35 - 14 = 21 researchers from the USA. The answer is 21.

[Question]Kathleen saved $21 in June, $46 in July, and $45 in August. Then Kathleen spent $12 on school supplies and $54 on new clothes. Kathleen's aunt said she would give Kathleen $25 if Kathleen saves more than $125. How much money does Kathleen have left?
[Answer]Kathleen saved $21 + $46 + $45 = $112. Kathleen's aunt did not give Kathleen any money because $112 is not greater than $125. Kathleen spent $12 + $54 = $66. Kathleen has $112 - $66 = $46 remaining. The answer is 46.

[Question]To get free delivery, Alice needs to spend a minimum of $35.00 online at her favorite grocery store. In her cart she has 1.5 pounds of chicken at $6.00 per pound, 1 pack of lettuce for $3.00, cherry tomatoes for $2.50, 4 sweet potatoes at $0.75 each, 2 heads of broccoli for $2.00 each and a pound of Brussel sprouts for $2.50. How much more does she need to spend in order to get free delivery?
[Answer]She bought 1.5 pounds of chicken for $6.00 / pound so that's 1.5 * $6 = $9.00. She bought 4 sweet potatoes at $0.75 each so that's 4 * $0.75 = $3.00. She bought 2 heads of broccoli for $2.00 each so that's 2 * $2 = $4.00. The chicken is $9.00, lettuce is $3.00, tomatoes are $2.50, the sweet potatoes are $3.00, broccoli is $4.00 and Brussel sprouts are $2.50 for a total of $9 + $3 + $2.50 + $3 + $4 + $2.5 = $24.00. To get free delivery she needs to spend $35.00, and she already has $24.00 in her cart, so she needs to spend an extra $35 - $24 = $11.00. The answer is 11.

[Question]Martha needs to paint all four walls in her 12 foot by 16 foot kitchen, which has 10 foot high ceilings. Each wall needs one coat of primer and two coats of paint. If Martha can paint 40 square feet per hour, how many hours will it take her to paint the kitchen?
[Answer]
There are two walls that are 12' X 10' and two walls that are 16' by 10'. First find the size in square feet of one 12' x 10' wall by multiplying the height and length: 12 ft * 10 ft = 120 sq ft. Multiply that quantity by 2 since there are two 12' x 10' walls: 120 sq ft * 2 = 240 sq ft. Then find the size in square feet of one 16' x 10' wall by multiplying the height and length: 16 ft * 10 ft = 160 sq ft. Multiply that quantity by 2 since there are two 16' x 10' walls: 160 sq ft * 2 = 320 sq ft. Now add the square footage of both sets of walls to find the total square footage Martha needs to paint: 240 sq ft + 320 sq ft = 560 sq ft. Now multiply that amount by 3 because Martha needs to add 3 coats: 560 sq ft / coat * 3 coats = 1680 sq ft. Finally, divide the total square footage by Martha's painting rate to find how many hours she needs to finish: 1680 sq ft / 40 sq ft / hour = 42 hours. The answer is 42.