Question: A pencil costs $0.5 each and a folder costs $0.9 each. An office needs two dozen pencils and 20 pieces of folders. How much does it cost to buy the office supplies?
Answer: Two dozens of pencils are equal to 2 x 12 = 24 pencils. So the total cost of pencils is $0.5 x 24 = $12. The total cost of folders is $0.9 x 20 = $18. Thus, the cost to buy the office supplies is $12 + $18 = $30. The answer is 30.
[Question]On Friday, Hank opened his used-bicycle store with a stock of bicycles, all fixed-up and ready to ride. Over the course of the day, he sold 10 bicycles and bought an additional 15 to fix up. On Saturday, he sold 12 bicycles and bought 8 more. And on Sunday, he sold 9 bicycles and bought 11 more. What was the net increase in the number of bicycles in stock in Hank's store over the three days?
[Answer]He sold 10 + 12 + 9 = 31 bicycles. He bought 15 + 8 + 11 = 34 bicycles. He now has 34 - 31 = 3 more than at Friday's opening. The answer is 3.
Q: In a triangle with angles A, B, and C, A is 60 degrees, and B is two times as big as C. Calculate the angle of B.
A: Since the angles in a triangle adds up to 180, and A is 40 degrees, B and C have a total of 180 - 60 = 120 degrees. Since B is two times bigger than C, the total of the angles of B and C is equal to 2C + C = 120. 3C = 120. The angle of C is C = 120 / 3. C is 40. Since B is two times as big as C, B is 2 * 40 = 80 degrees. The answer is 80.
Question: Martha has 18 crayons. She lost half of them, so she bought a new set of 20 crayons. How many crayons in total does Martha have after the purchase?
Answer: In the beginning, Martha lost 18 / 2 = 9 crayons. So after she bought a set of new crayons, she has in total 9 + 20 = 29 crayons. The answer is 29.
[Question]Jerry has a bunch of half-empty soda cans on his desk. He needs to drain all of them and put them in the recycling bin. He can carry four cans at once, and it takes him 30 seconds to drain those 4 cans. It takes him ten seconds each way to walk to the sink and recycling bin and then back to his desk. If there are 28 cans on Jerry's desk, how long does it take him to throw all of them away?
[Answer]Jerry has to walk to the sink / recycling bin 28 cans / 4 cans per trip = 7 trips. The round trip takes 10 seconds per way * 2 ways = 20 seconds. Counting the time he spent pouring out the cans and the time the round trip took, he spent 20 seconds per trip + 30 seconds per trip = 50 seconds per trip. With 7 round trips, he spent 50 seconds per trip * 7 trips = 350 seconds. The answer is 350.
[Question]At a birthday party, there are 20 red balloons and 15 green balloons. Before the party started, 3 red and 2 green balloons burst. How many balloons are left?
[Answer]
There are a total of 20 + 15 = 35 balloons at the party. Out of the 35, 3 + 2 = 5 balloons burst. Thus, only 35 - 5 = 30 balloons are left. The answer is 30.