hardmath

Can you find the last number in the number sequence given below? 10 : 10 : 20 : 45 : 110 : 300 : ?

930 Explanation: New number = Last number * multiplication factor (increased by 0.5 every time) + sum factor (increased by 5 every time) 10 10 * 0.5 + 5 => 10 10 * 1.0 + 10 => 20 20 * 1.5 + 15 => 45 45 * 2.0 + 20 => 110 110 * 2.5 + 25 => 300 300 * 3.0 + 30 => 930 , desired answer

Why this works

This riddle involves a sequence where each number is generated using a specific formula that combines multiplication and addition, both of which change incrementally. Starting from 10, each subsequent number is calculated by multiplying the last number by a factor that increases by 0.5 each time, and then adding a sum that increases by 5. For instance, to find the last number, we apply the pattern: for 300, we multiply by 3.0 and add 30, resulting in 930. By breaking down the logic step by step, we can see how each part of the formula contributes to the next number in the sequence, making the final answer not only reasonable but also consistent with the established pattern.

Common Wrong Answers

“600”

The guess 600 does not account for the increasing multiplication and sum factors applied at each step in the sequence.

“800”

The guess 800 fails to follow the established pattern of multiplying by an increasing factor and adding a progressively larger sum.

“750”

The guess 750 ignores the required calculations based on the previous number and the specific factors that contribute to each new number in the sequence.

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