A Nice Olympiads Simplification Trick | No Calculator Allowed

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[@JustinGreene-r9o]

It is much simpler to not use "m" at 4:13. Simply start easier multiplication there.

[@rabotaakk-nw9nm]

3:50 8•49•50+7= =400(50-1)+7=20000-400+7=19607

[@arupmallik3070]

Unnecessary lengthened the problem by using substitute.