Answer:
The18th term of the given sequence is -128
Explanation:
To find the 18th term of the sequence:
42, 32, 22, 12, ..., we need to find the nth term of the sequence first.
The nth term of a sequence is given be the formula:

Where a is the first term, and d is the common difference.
Here, a = 42, d = 32 - 42 = -10

To find the 18th terem, substitute n = 18 into the nth term
I think the correct answer is 17
10 goes into 67 six times making it 6 7/10, which cannot be simplified. Therefore, if can be left as it is, an improper fraction 67/10, or a mixed number 6 7/10.
Convert <span>6\frac{3}{8}<span>6<span><span>8</span><span>3</span><span></span></span></span></span><span> to improper fraction. Use this rule: </span><span>a \frac{b}{c}=\frac{ac+b}{c}<span>a<span><span>c</span><span>b</span><span></span></span>=<span><span>c</span><span><span>ac+b</span></span>:</span></span></span>
∣8<span><span><span><span>6×8+3</span></span><span></span></span>−2∣+∣−8<span><span>8</span><span>5</span><span></span></span>−1<span>∣
</span></span>Simplify <span>6\times 8<span>6×8</span></span><span> to </span>48: <span><span><span><span><span>
</span>8</span><span><span>48+3</span></span><span></span></span>−2∣+∣−8<span><span>8</span><span>5</span><span></span></span>−1∣
</span>Simplify <span>48+3<span>48+3</span></span><span> to </span>51:</span><span><span><span><span><span>
</span>8</span><span><span>51</span></span><span></span></span>−2∣+∣−8<span><span>8</span><span>5</span><span></span></span>−1∣
</span> Make the denominators the same:
<span><span><span>51</span><span>/8</span></span>−2×<span><span>8</span><span>8</span><span>
</span></span></span><span>Simplify. Denominators are now the same:
</span>
<span><span><span>51</span><span>/8</span></span>−<span><span>8</span><span><span>16</span></span><span>
</span>
</span></span>Join the denominators: \frac{51-16}{8}<span><span>8</span><span><span>51−16</span></span><span>
</span>
etc.. and your answer will be 14
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