A₁ = 9
a₂ = 9+2 → a₂ = a₁ + 2. Since it's an AP, d, the common difference is 2
1) Then the recursive formula is :
a(n) = a(n-1) + 2
2) Explicit formula:
It's an AP, with first term a₁, d= common difference and n = number of term, which is the number of rows in this problem.
the value of the nth term is given by the formula is:
value of nth term = a₁ + (n-1).d
3) Number of seats in the 12th row:
9 + (12-1).2 = 31 seats
<span>10q + 5 = 5q + 5q + 5
so
answer is
</span><span>
A. 5q+5q+5</span>
The correct answer should be :
Option 3 : 
Hope this helps,
Davinia.
The mean is the average of the numbers: a calculated "central" value of a set of numbers.
Therefore: If the amount spent on books per month by all her classmates is leveled that amount would be $30
To calculate it: add up all the numbers, then divide by how many numbers there are
