Select the option that will replace the question mark (?) in the given series.
78, 89, 82, 87, 84, ?
Prime numbers are added and subtracted from each term on the alternative basis which is given below.
78+11 = 89
89-7 =Â 82
82+5 = 87
87-3 = 84
84+2 = 86
Hence '86' will come in place of the question mark.
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