Q: Timothy has $50 to spend at a souvenir shop. He sees some t-shirts that cost $8 each, key chains that sell 3 pieces for $2, and bags that cost $10 each. Timothy buys 2 t-shirts and 2 bags. How many pieces of key chains can he buy with the amount of money he has left?
A: The two t - shirts amount to $8 x 2 = $16. The two bags amount to $10 x 2 = $20. So Timothy spent $16 + $20 = $36 for the shirts and bags. He still has $50 - $36 = $14 left to spend for the key chains. With the money, he can buy $14 / $2 = 7 sets of key chains. Therefore, he can buy 7 x 3 = 21 pieces of key chains. The answer is 21.

Q: Ten more than twice the number of birds on the fence is 50. How many birds are on the fence?
A: Let x be the number of birds on the fence. We know that 10 + 2 * x = 50. Subtracting 10 from both sides, we get 2 * x = 50 - 10 = 40. Dividing both sides by 2, we get x = 20. The answer is 20.

Q: Amy bakes muffins for her friends. On Monday, she brings 1 muffin to school to share. Each day for the rest of the week she brings one more muffin to school than she did the day before. If on Saturday she counts that there are 7 muffins left, how many did she originally bake?
A:

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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On Tuesday, she brings in 1 + 1 = 2 muffins. On Wednesday, she brings in 2 + 1 = 3 muffins. On Thursday, she brings in 3 + 1 = 4 muffins. On Friday, she brings in 4 + 1 = 5 muffins. In total, she brought 1 + 2 + 3 + 4 + 5 = 15 muffins to school to share with her friends. She baked a total of 15 + 7 = 22 muffins. The answer is 22.