You can put this solution on YOUR website! Series appears to be like 2+12+22+32+... ADDED TO 7+17+27+37+...
OR
The series for ADDED TO the series for .
If you want the series for the first 10 terms, then
using the arithmetic sum formula
.
....
Do the sum of both of these for their FIRST FIVE TERMS.
Use sum of arithmetic series formula.
Let me re-formulate the question / the problem in more clear way:
Find the sum S10 of the first 10 members of the sequence 2, 7, 12, 17, . . .
Solution
It is an arithmetic progression with the first term of 2 and the common difference of 5.
The sum of the first 10 terms is = = (2+22.5)*10 = 24.5*10 = 245.
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