n starts at 1, and n is a positive whole number (1,2,3,...)
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Explanation:
The sequence is arithmetic with first term 40 and common difference 10. Meaning we add 10 to each term to get the next one.
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a1 = 40 = first term
d = 10 = common difference
[tex]a_n = a_1 + d(n-1)\\\\a_n = 40 + 10(n-1)\\\\a_n = 40 + 10n-10\\\\a_n = 10n + 30\\\\[/tex]
is the general nth term of this arithmetic sequence
Plug in n = 1 and you should get [tex]a_1 = 40[/tex]
Plug in n = 2 and you should get [tex]a_2 = 50[/tex]
and so on