What is the 31th term of the arithmetic sequence 10,5,0,-5,-10....? An=a1+(n-1)d a31=10+(31-1)(-5) a31=5+(30)(-5) a31=5+(-150) a31=-145
the common difference is -5
10 + [30 (-5)] = ?
To find the 31st term of an arithmetic sequence, we can use the formula:
An = a1 + (n-1)d
where An is the nth term, a1 is the first term, n is the term number, and d is the common difference.
Given that the first term (a1) is 10 and the common difference (d) is -5, we can substitute these values into the formula:
A31 = 10 + (31 - 1)(-5)
Simplifying further:
A31 = 10 + (30)(-5)
A31 = 10 + (-150)
A31 = -140
Therefore, the 31st term of the arithmetic sequence 10, 5, 0, -5, -10, ... is -140.