[Question]John buys 4 pounds of beef. He uses all but 1 pound in soup. He uses twice as many pounds of vegetables as beef. How many pounds of vegetables did he use?
[Answer]He used 4 - 1 = 3 pounds of beef. So he used 3 * 2 = 6 pounds of vegetables. The answer is 6.
Q: A party of 4 order 3 dozen oysters on the half shell for $15.00 a dozen, 2 pounds of steamed shrimp for $14.00 a pound and 2 pounds of fried clams for $13.50 a pound. If they split the bill equally, how much will they each owe?
A: They ordered 3 dozen oysters at $15.00 a dozen so that's 3 * 15 = $45.00. They ordered 2 pounds of shrimp for $14.00 a pound so that's 2 * 14 = $28.00. They ordered 2 pounds of fried clams for $13.50 a pound so that's 2 * 13.50 = $27.00. All total their bill comes to 45 + 28 + 27 = $100.00. Their bill was $100.00 and they are splitting it equally amongst 4 people so they each owe 100 / 4 = $25.00. The answer is 25.
Question: Jane, Kyla, and Anthony have summer jobs in a resort. Their task is to fold guests' towels. Jane can fold 3 towels in 5 minutes. Kyla can fold 5 towels in 10 minutes, and Anthony can fold 7 towels in 20 minutes. If they all fold towels together, how many towels can they fold in one hour?
Answer: There are 1 x 60 minutes = 60 minutes in 1 hour. There are 60 / 5 = 12 sets of 5 minutes in 1 hour. So, Jane can fold 3 x 12 = 36 towels in an hour. There are 60 / 10 = 6 sets of 10 minutes in 1 hour. So, Kyla can fold 5 x 6 = 30 towels in an hour. There are 60 / 20 = 3 sets of 20 minutes in 1 hour. So, Anthony can fold 7 x 3 = 21 towels in an hour. Therefore, the 3 of them can fold a total of 36 + 30 + 21 = 87 towels in 1 hour. The answer is 87.
[Question]Tim is 5 years old. His cousin, Rommel, is thrice as old as he is. His other cousin, Jenny, is 2 years older than Rommel. How many years younger is Tim than Jenny?
[Answer]Rommel is 5 x 3 = 15 years old. Jenny is 15 + 2 = 17 years old. So, Tim is 17 - 5 = 12 years younger than Jenny. The answer is 12.
Q: John decides to trade in his stereo system. His old system cost 250 dollars and he got 80% of the value for it. He then buys a system that costs $600 that he gets a 25% discount on. How much money came out of his pocket?
A: He got 250 * .8 = $200. He gets a 600 * .25 = $150 discount on the second system. So it cost 600 - 150 = $450. So he was 450 - 200 = $250 out of pocket. The answer is 250.
Question: Lizzy's school choir has a mixture of 80 blonde and black-haired girls. Their teacher decides to add 10 more girls to the choir, who turns out to be blonde. If there were 30 blonde-haired girls in the choir initially, how many black-haired girls are present?
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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The total number of girls in the choir is 80 + 10 = 90 girls. The total number of blondes in the choir after 10 more are added is 30 + 10 = 40 blonde - haired girls. From the total number, the number of black - haired girls is 90 - 40 = 50 black - haired - girls. The answer is 50.