Use commutative, associative, and distributive structure to rewrite and simplify numerical expressions efficiently.
Choose the best property-based rewrite
Problem
Rewrite \(99~\times~7\) in the most efficient way you can using a number property. Then find the value.
Big Picture
What this problem is really about
Ninety-nine is close to a friendlier factor, one hundred, but using that factor adds one extra group of seven. We’ll rewrite ninety-nine as one hundred minus one, distribute the multiplication across the difference, and subtract the extra group. That preserves the original product while making the arithmetic easier.
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