please experts,,,,,,,,,,,please help me out through this,,,,
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please experts,,,,,,,,,,,please help me out through this,,,,,, 3,5,-5.... the first term shown in the sequence is 3 each even numbered term is 2 more than the previous term and odd numbered term, after the first is -1 times the previous term .what is 51st term in the sequence???
- VivianKerr
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Let's look for a pattern:
3, 5, -5...
following their description, the next sequence would continue:
...-3, 3, 5, -5
The 4th term is -3 because it's an even-numbered term and -5 + 2 = -3.
The 5th term is 3 because it's an odd-numbered term and -3 x -1 = 3.
Putting the entire sequence together, we can see a pattern:
3, 5, -5, -3, 3, 5, -5...
There are only 4 unique terms and they repeat on a cycle.
4 divides into 51 evenly 12 times. (12 x 4 = 48), so the cycle will complete on the 48th term.
49th term will then start it again, and be 3.
50th term will be 5.
51st term will be -5.
3, 5, -5...
following their description, the next sequence would continue:
...-3, 3, 5, -5
The 4th term is -3 because it's an even-numbered term and -5 + 2 = -3.
The 5th term is 3 because it's an odd-numbered term and -3 x -1 = 3.
Putting the entire sequence together, we can see a pattern:
3, 5, -5, -3, 3, 5, -5...
There are only 4 unique terms and they repeat on a cycle.
4 divides into 51 evenly 12 times. (12 x 4 = 48), so the cycle will complete on the 48th term.
49th term will then start it again, and be 3.
50th term will be 5.
51st term will be -5.
Vivian Kerr
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GMAT Rockstar, Tutor
https://www.GMATrockstar.com
https://www.yelp.com/biz/gmat-rockstar-los-angeles
Former Kaplan and Grockit instructor, freelance GMAT content creator, now offering affordable, effective, Skype-tutoring for the GMAT at $150/hr. Contact: [email protected]
Thank you for all the "thanks" and "follows"!
![Smile :-)](./images/smilies/smile.png)