a teacher wants to determine the seating capacity of a gymnasium with 18. seats on the first row 20 in the second ,22 on the third .the sequence of the seating capacity per row continues until the 14th row.how many is the seating capacity of gymnasium

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OnekPHid OnekPHid · Answer 1

Answer:

434

Step-by-step explanation:

If

a2-a1= a3-a2, commmon difference the same it is an Arithmetic Progression

20-18=22-20

2=2, so it is an AP

First solve a14, using the formula

a14=a1+(14-1)d, where d is 2

Then substitute,

a14 = 18+13(2)

a14=44

The formula for the sum in an AP is

Sn= n/2 x (a1+an)

Then,

S14 = 14/2 x (18+44)

S14=434 ( the total amount of seat or the capacity of the auditorium).

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