Multiple choice

Directions: Find the missing value in the following number series. 6, 5, 13, 35, 20, 245, 27, ?

  1. 1715

  2. 1470

  3. 1960

  4. 1225

  5. None of these
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

The series is alternating operations: 6-1=5, 5*2.6=13 (no), 6-1=5, 5+8=13, 13*2.69=35 (no). Looking at pairs: (6,5), (13,35), (20,245), (27,?). The pattern is: 6*2+1=13, 13*2-6=20, 20*2-13=27. The second numbers are 5, 35, 245. 5*7=35, 35*7=245, 245*7=1715.

AI explanation

The given sequence is an alternating series where odd-positioned terms (6, 13, 35, 20, 245, 27) appear to serve as multipliers or addends, and the even-positioned terms (5, 35, 245) are generated by multiplying the previous even term by 7. Since 5 x 7 = 35 and 35 x 7 = 245, the next even-positioned term is 245 x 7 = 1715.

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