SOLUTION: The theater has 35 seats in the 1st row, 45 in the 2nd row and 55 in the 3rd row and so on.
A. What is the common difference?
B. How many seats are there in the 25th row?
C. W
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-> SOLUTION: The theater has 35 seats in the 1st row, 45 in the 2nd row and 55 in the 3rd row and so on.
A. What is the common difference?
B. How many seats are there in the 25th row?
C. W
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Question 1088620: The theater has 35 seats in the 1st row, 45 in the 2nd row and 55 in the 3rd row and so on.
A. What is the common difference?
B. How many seats are there in the 25th row?
C. Which row has 205 seats? Answer by ikleyn(52903) (Show Source):
You can put this solution on YOUR website! .
The theater has 35 seats in the 1st row, 45 in the 2nd row and 55 in the 3rd row and so on.
A. What is the common difference? The common difference is d = 45 - 35 = 10.
B. How many seats are there in the 25th row? = + (25-1)*d = 35 + 24*10 = 35 + 240 = 275.
C. Which row has 205 seats? = + (n-1)*d = 35 + 10*(n-1) = 205.
Solve it for n: 10(n-1) = 205-35 = 170 ====> n-1 = 17 ====> n = 18.
Answer. 18-th row has 205 seats.
