2024 AMC 10A Problem 1

Problem 1 of 25EasierAlgebra

What is the value of

9901 \cdot 101 - 99 \cdot 10101?

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Solution

Just compute each piece. We have

9901 \cdot 101 = 990100 + 9901

= 1000001,

and

99 \cdot 10101 = 999999.

Subtracting,

1000001 - 999999 = 2.

Thus, A is the correct answer.

Concepts: whole number operations

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