posted by Lindsay on .
The first row of a concert hall has 25 seats and each row after the first has one more seat than the row before it. There are 2 rows of seat. 1)Write a rule for the number of seats in the nth row.
2)35 students from a class want to sit in the same row. How close to the front can they sit?
The statement, "There are 2 rows of seat" , is confusing.
Is there a front row of 25, then an aisle, and another 25 seats for the entire first row ???
Please be more specific.
Once that is cleared it looks like a simple arithmetic sequence question
a = 25
d = 1
Sorry...there are 32 rows of seats
Now it is very easy
tn = a+(n-1)d
= 25 + (n-1)(1)
= 24 + n
so which row comes closest to 35 ?
The 35 students can sit all in row 11
Thanks! I knew it was row 11 but didn't know how to write a formula to prove it...