SOLUTION: What is the 15 terms of the arithmetic progression whose first term is 6and common difference is 7

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Question 1205594: What is the 15 terms of the arithmetic progression whose first term is 6and common difference is 7
Found 2 solutions by MathLover1, ikleyn:
Answer by MathLover1(20850) About Me  (Show Source):
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the arithmetic progression general formula is
a%5Bn%5D=a%5B1%5D%2Bd%28n-1%29
given that a%5B1%5D=6 and d=7

a%5Bn%5D=6%2B7%28n-1%29
now find the 15 terms
we know first term, so second term is
n=2
a%5B2%5D=6%2B7%282-1%29=13
third term will be
n=3
a%5B3%5D=6%2B7%283-1%29=6%2B14=20
or simply find the next term by adding common difference to previous term
a%5B4%5D=27
a%5B5%5D=34
a%5B6%5D=41
a%5B7%5D=48
a%5B8%5D=55
a%5B9%5D=62
a%5B10%5D=69
a%5B11%5D=76
a%5B12%5D=83
a%5B13%5D=90
a%5B14%5D=97
a%5B15%5D=104
so, first 15 terms are:
6,13,20,27,34,41,48,55,62,69,76,83,90,97,104



Answer by ikleyn(52788) About Me  (Show Source):
You can put this solution on YOUR website!
.
What is the fifteenth highlight%28cross%28terms%29%29 term of the arithmetic progression
whose first term is 6 and common differences is 7
~~~~~~~~~~~~~~~~~~~ 

It is 

    6 + (15-1)*7 = 104.    ANSWER

Solved.

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For introductory lessons on arithmetic progressions see
    - Arithmetic progressions
    - The proofs of the formulas for arithmetic progressions
    - Problems on arithmetic progressions
    - Word problems on arithmetic progressions
in this site.