What is the sum of the arithmetic sequence 9, 14, 19, , if there are 32 terms?

2,768

2,800

2,832

2,864

Question

What is the sum of the arithmetic sequence 9, 14, 19, , if there are 32 terms?


		
2,768
		
2,800
		
2,832
		
2,864

anonymous · Answer

a=9
d= 19-14=
     =14-9
      = 5 

finding 32nd term-
a_n=a+(n-1)d
      = 9+(31)5
 32nd or last term = 164

Now sum of n terms=
S_n = n/2 * (a+l)  ,l=last term
therefore, S_32 = 32/2 * (9+164)
                        = 16 * 173
                         = 2768

anonymous · Answer

Okay i understand why the end works but i dont understand the beginning specifically d

anonymous · Answer

d is the common difference between any two consecutive no.

anonymous · Answer

so i can use that equation for any problem like that correct?

anonymous · Answer

yes

anonymous · Answer

Wait what does N stand for

anonymous · Answer

n is any no. .