Question
55, 71, 119, 199, 311,
? Find the missing number in the given number seriesΒSolution
Calculate the differences between consecutive terms: 71β55=16 119β71=48 199β119=80 311β199=112 The differences are 16,48,80,112. The second-order differences (differences of the differences) are constant: 48β16=32 80β48=32 112β80=32 Since the second-order differences are constant, the next difference is: 112+32=144 Adding this to the last term:311+144 = 455
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