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Identify the next term in the following number series: $3, 7, 16, 35, 74, ?$\nA) 149\nB) 151\nC) 153\nD) 155
The correct answer is C) 153.\n\nLet the given number series be denoted by $S = \{t_1, t_2, t_3, t_4, t_5, \ldots\}$.\nWe have $t_1 = 3$, $t_2 = 7$, $t_3 = 16$, $t_4 = 35$, $t_5 = 74$.\nWe need to find $t_6$.\n\n**Step 1: Analyze the differences between consecutive terms (First Layer Differences).**\nLet $D_n = t_{n+1} - t_n$.\n$D_1 = t_2 - t_1 = 7 - 3 = 4$\n$D_2 = t_3 - t_2 = 16 - 7 = 9$\n$D_3 = t_4 - t_3 = 35 - 16 = 19$\n$D_4 = t_5 - t_4 = 74 - 35 = 39$\nThe sequence of first layer differences is $D = \{4, 9, 19, 39, \ldots\}$.\n\n**Step 2: Analyze the differences between consecutive terms in the First Layer Differences (Second Layer Differences).**\nLet $D'_n = D_{n+1} - D_n$.\n$D'_1 = 9 - 4 = 5$\n$D'_2 = 19 - 9 = 10$\n$D'_3 = 39 - 19 = 20$\nThe sequence of second layer differences is $D' = \{5, 10, 20, \ldots\}$.\n\n**Step 3: Identify the pattern in the Second Layer Differences.**\nThe sequence $D' = \{5, 10, 20, \ldots\}$ is a Geometric Progression (GP) where each term is obtained by multiplying the previous term by 2.\nThe common ratio ($r$) is $\frac{10}{5} = 2$ and $\frac{20}{10} = 2$.\nThus, the next term in $D'$ would be $D'_4 = 20 \times 2 = 40$.\n\n**Step 4: Determine the next term in the First Layer Differences.**\nUsing the identified pattern, the next term in the first layer differences, $D_5$, can be calculated:\n$D_5 = D_4 + D'_4 = 39 + 40 = 79$.\n\n**Step 5: Calculate the next term in the original series.**\nThe next term in the original series, $t_6$, is obtained by adding $D_5$ to $t_5$.\n$t_6 = t_5 + D_5 = 74 + 79 = 153$.\n\nTherefore, the next term in the series is $153$.
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