[Question]Trey is hanging wall decorations around his house. He uses a nail for each of two-thirds of them, a thumbtack for each of two-fifths of the rest, and a sticky strip for each of the other decorations. He used 15 sticky strips. How many nails did Trey use?
[Answer]Trey used 15 sticky strips for 3 / 5 of the remaining decorations after using nails, so he used 15 *  / 3 / 5 = 25 thumbtacks and sticky strips. The 25 decorations were 1 / 3 of the total decorations, so he used 25 / 1 / 3 = 75 total decorations. The nails were 2 / 3 of the decorations, so Trey used 75 decorations * 2 / 3 = 50 nails. The answer is 50.
Q: On a normal day, Julia can run a mile in 10 minutes. However, today she decided to wear her new shoes to run. They were uncomfortable and slowed her mile down to 13 minutes. How much longer would it take Julia to run 5 miles in her new shoes than if she wore her old ones?
A: With her regular shoes, it should take 5 * 10 = 50 minutes to run five miles. If she wore her new shoes it would take 13 * 5 = 65 minutes to run five miles. 65 - 50 = 15 more minutes. The answer is 15.
Question: James is trying to avoid eating too much sodium. He's making a recipe that calls for 2 teaspoons of salt and 8 oz of parmesan cheese. Salt has 50 mg of sodium per teaspoon and parmesan has 25 mg of sodium per oz. If he can't reduce the salt, how many fewer ounces of parmesan cheese does he need to use to reduce the total amount of sodium by 1/3rd?
Answer: First find how much sodium the parmesan has in total by multiply the amount of sodium per ounce by the number of oz: 25 mg / oz * 8 oz = 200 mg. Then use the same process to find how much sodium is in the salt: 50 mg / tsp * 2 tsp = 100 mg. Then find the total sodium in the recipe by adding the sodium from the cheese and the salt: 100 mg + 200 mg = 300 mg. Then multiply the total amount of sodium by 1 / 3 to find how much less sodium James wants: 300 mg * 1 / 3 = 100 mg. Then divide this amount by the amount of sodium per ounce of cheese to find how many fewer ounces of cheese he needs: 100 mg / 25 mg / oz = 4 oz. The answer is 4.
[Question]At a birthday party, 30% of the guests are married, 50% are single, and the rest are children. If there are 1000 guests, how many more married people are there than children?
[Answer]There are 1000 x 30 / 100 = 300 people who are married. There are 1000 x 50 / 100 = 500 people who are single. So, there are a total of 300 + 500 = 800 that are either married or single. This means, 1000 - 800 = 200 are children. Therefore, there are 300 - 200 = 100 more married people than children. The answer is 100.
Q: Amber is baking cakes for her party. She has invited 8 friends and each one will want two slices of cake. Each cake makes 6 slices. If she bakes 4 cakes, how many slices will be left over at the end if she eats three herself?
A: Her friends will eat 16 slices of cake because 8 x 2 = 16. There will be 19 slices eaten in total because 16 + 3 = 19. She is making 24 slices of cake because 4 x 6 = 24. There will be 5 pieces left over because 24 - 19 = 5. The answer is 5.
Question: Cara is at her family reunion, where she discovers that she is 20 years younger than her mom. Her mom is 15 years younger than Cara's Grandmother. If Cara's grandmother is 75, how old is Cara?
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.
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Cara's mom: 75 - 15 = 60 years old. Cara: 60 - 20 = 40 years old. The answer is 40.