Answer: 17
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Work Shown:
a1 = 3 = first term
d = 2 = common difference (since we add 2 to each term to get the next one)
Let's compute the nth term.
an = a1 + (n-1)*d
an = 3 + (n-1)*2
an = 3 + 2n-2
an = 2n+1
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To check things so far, we can plug in something like n = 2
an = 2n+1
a2 = 2*2+1
a2 = 5
Showing that the 2nd term is 5, which matches with the sequence given to us
Let's check n = 3
an = 2n+1
a3 = 2*3+1
a3 = 7
That matches as well. I'll let you check the others.
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Plug in n = 8 to find the 8th term
an = 2n+1
a8 = 2*8+1
a8 = 17
The eighth term is 17, which is the final answer.
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You could extend out the given sequence by adding 2 each time until you reach the 8th term
3,5,7,9,11,13,15,17
Though this method is slow if you need to find say the 38th term