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Question Number 220739 by Spillover last updated on 18/May/25
Answered by mr W last updated on 18/May/25
$$\left.\mathrm{1}\right) \\ $$$$\frac{\mathrm{7}!}{\mathrm{2}!\mathrm{2}!}=\mathrm{1260} \\ $$$$\left.\mathrm{2}\right) \\ $$$$\mathrm{1260}−\mathrm{2}×\frac{\mathrm{6}!}{\mathrm{2}!\mathrm{2}!}=\mathrm{1260}−\mathrm{360}=\mathrm{900} \\ $$$${or} \\ $$$$\frac{\mathrm{5}!}{\mathrm{2}!\mathrm{2}!}×\mathrm{6}×\mathrm{5}=\mathrm{900} \\ $$