Question: Paul makes pencils, making 100 pencils a day five days a week. He started the week with 80 pencils in his stock, and during the week he sold 350 pencils. How many pencils did he have in his stock at the end of the week?
Answer: Making 100 pencils a day, he made 100 pencils / day * 5 days / week = 500 pencils during the week. With the pencils from the stock, he got 500 pencils + 80 pencils = 580 pencils. Subtracting the ones he sold, he has 580 pencils - 350 pencils = 230 pencils. The answer is 230.
[Question]Joe's pizzeria has an amazing promotion. If you buy any regular large pizza you can get the next 3 medium pizzas for $5 each. What are your total savings if the regular medium pizza price is $18 and you take full advantage of the promotion?
[Answer]If one medium pizza costs $18 and with the promotion I can buy one for $5, then I'm saving $18 - $5 = $13 on each medium pizza. If I take full advantage of the promotion, that means I bought all 3 medium pizzas, therefore I saved a total of 3 * $13 = $39 in total. The answer is 39.
Q: Jeff orders a Halloween costume. He has to put in a 10% deposit and then pay the rest when he picks it up. The costume is 40% more expensive than last year's costume, which cost $250. How much did he pay when picking it up, in dollars?
A: It cost 250 * .4 = $100 more than his old costume. So it cost 250 + 100 = $350. He left a 350 * .1 = $35 deposit. So he had to pay 350 - 35 = $315. The answer is 315.
Question: Justin can run 2 blocks in 1.5 minutes. If he is 8 blocks from home, in how many minutes can he run home?
Answer: There are 8 / 2 = 4 sets of two blocks that Justin can run. Thus, he can run home for 4 x 1.5 = 6 minutes. The answer is 6.
[Question]Kerry is ready to celebrate his birthday and wants to have three cakes with his age in candles on each of them. Candles come in boxes of 12 and cost $2.5 a box. If the candles cost $5, how old is Kerry?
[Answer]He needed 2 boxes of candles, because 5 / 2.5 = 2. He needed 24 candles because 2 x 12 = 24. He is 8 because 24 / 3 = 8. The answer is 8.
[Question]Rachel is twice as old as Rona and Collete's age is half the age of Rona's. If Rona is 8 years old, what is the difference between the age of Collete and Rachel?
[Answer]

Show your work and conclude with the exact phrasing "Therefore, the final answer is [answer]." where [answer] is just the final number or expression that solves the problem.
user
Rachel's age is 8 x 2 = 16. Collete's age is 8 / 2 = 4. Therefore the difference between their age is 16 - 4 = 12. The answer is 12.