Level
pending

The answer is 0.5.

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Let's set this term to x. Then, 1 - x equals 1 - (1-1+1...). Distributing 1-x yields equals 1-1+1-1+1 ... . Here's where the magic begins. The term on the right side is equivalent to x. There fore, 1 - x = x --> 2x = 1. Dividing gives x = 0.5.