This is an Arithmetic Progression with 1st term 11 and common difference d=6
Number of Rows Number of seats Common difference " d"
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1st a₁ = 11
2nd a₁+d =17 d =2nd - 1st = 6
3rd a₁ +2d = 23 d =3rd - 2nd = 6
4th a₁ +3d = 29 d= 4th - 3rd = 6
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nth ROW a(n) = a₁ + (n-1)d
18th ROW a₁₈ = 11 + (18-1).6 = 11+(17)(6) = 113
General equation to predict the number of seat an the nth row:
Number of seats in nth row = a₁ + (n-1).d
So far your getting all of them right. But, maybe next time upload a better picture because it’s hard to see what you wrote.
Answer:
64
Step-by-step explanation:
The common difference is 80 / (8 - 3)
= 16
So f(18) - f(14) = (18 - 14) * 16
= 54
I think Its 6.............
