Brain Teasers & Mental Math
Fraction/ratio estimation: a company has revenue of $4.2bn and you estimate net margin around 11%. Roughly what is net income?
Model answer
About $460 million.
Estimate by anchoring on 10%: 10% of $4.2bn = $420M. The extra 1% adds $42M, so 11% ≈ $420M + $42M = $462M. Round to ~$460M.
Mental-math…
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