This is the sum an arithmetic sequence which is the average of the first and last terms times the number of terms
Te first term is 15
the 36th term is 15+ 35(3)= 120
therefore you have (15+120)(36)/2= 243-
Amelian R.
Where did the 35 and the 3 come from?
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05/23/21
Amelian R.
And how do i find the number of seats in the last row? Thanks for the help
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05/23/21
Stephen K.
tutor
3 is the common difference between terms. Each term in this sequence is 3 more than the previous term
35 is the number of times you need to add 3 to the initial term
The nimbus of seats in the 36th row is 15 + 3(35)=120
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05/23/21
Stephen K.
05/19/21