<p>3,5,-5....</p>
<p>The first term in the sequence of numbers shown above is 3. Each even-numbered term is 2 more than the previous term and each odd-numbered term, after the first is -1 times the previous term. For example, the second term is 3+2, and the third term is (-1) x 5. What is the 55th term in the sequence.</p>
<p>A. -5
B. -3
C. -1
D. 3
E. 5</p>
<p>The answer is A but is there a short way to do this because what I did too way too long</p>
<p>Well look for a pattern</p>
<p>3,5,-5,-2,2,5,-5,-2,2</p>
<p>So there are 55 terms, the first is the only unique non repeated one, so do
55-1, =54, now, the sequence repeats 5,-5,-2,2, so divide 54/4, you get 13.5 which means it will repeat 13 times and will land on the 2nd term of the 4 numbers (since .5 = 2/4), so it will land on -5,</p>
<p>there is you're answer</p>
<p>Just a question about your sequence it says "Each even-numbered term is 2 more than the previous term." So Wouldn't -5 + 2 be -3 not -2? or am i missing something</p>
<p>oh, I accidentally worked it out as +3, let me redo it</p>
<p>ok, look for the pattern</p>
<p>3,5,-5,-3,3, so the set 3,5,-5,-3 repeats, divide 55/4, you get 13.75, so it repeats 13 times and lands on the third term of the four term group, so that would be -5</p>
<p>There</p>