Which of the following does not fit in the series?
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Which of the following does not fit in the series?
4/5, 7/15, 1/15, -1/5, -8/15
Show answer & explanation
Answer: A. A) 1/15
Expressed with denominator 15, the series is 12/15, 7/15, 2/15, -3/15, -8/15 with a common difference of -5/15. The term 1/15 violates this progression (it should be 2/15).
Step-by-step Derivation:
Step 1: Common denominator 15: 12/15, 7/15, [term], -3/15, -8/15.
Step 2: Notice difference between consecutive terms: 12 - 5 = 7, and -3 - 5 = -8.
Step 3: The middle term should be 7 - 5 = 2/15.
Step 4: The given term is 1/15, which is incorrect.