What is the sum of the arithmetic sequence 6, 11, 16 …, if there are 24 terms?

Question

anonymous · Answer

the common difference is 5,first term is 6..so at first find the 24th term..

anonymous · Answer

There are 2 approaches:   first, you can simply use the formula for arithmetic series (i.e. sum of the sequence) ----   sum =  24 (a1 + a24)/2...   a1 is 6    and,   a24  is  23(5) + 6 = 121...

anonymous · Answer

But, if you want to view it intuitively, consider this:   the first term is 6 and the last term is 121...  6 + 121 = 127...   the second term is 11 and the 23rd term is 116...  11 + 116 = 127...  so, every pair is 127....  And, there are  12 pairs...    12 pairs x 127 = 1524