Mathematics
Problem of The Day
2025
171

171

George hid the middle of this sequence:

1000 1 ? ? 50 2.718

But Cicero mentioned that the same number is missing twice.

What is the number?

‍

Answer

500

SOLUTIOn

1000, 1, ?, ?, 50, 2.718

The same number is missing twice. The sentence says: “George hid the middle of this sequence.” Cicero is mentioned too. What’s the missing number?

Solution:

The key is in the word “middle.” If you look closely, it contains the letter D twice.

The word "middle" is spelled with the following letters:

M, I, D, D, L, E

Among these, several letters correspond to Roman numerals:

M = 1000

I = 1
L = 50

And E is just 2.718..

So if two Ds are “hidden” in the middle, it suggests that two 500s are missing from the sequence.

Filling them in:

1000, 1, 500, 500, 50, 2.718

Everything fits. Two identical numbers are missing, and the clue was in the wording all along.

Answer: 500

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