Question Number 877 by sagarwal last updated on 07/Apr/15 $$\mathrm{An}\:\mathrm{8}×\mathrm{8}\:\mathrm{checkerboard}\:\mathrm{is}\:\mathrm{to}\:\mathrm{be}\:\mathrm{coloured} \\ $$$$\mathrm{with}\:\mathrm{6}\:\mathrm{colors}\:\:\mathrm{in}\:\mathrm{a}\:\mathrm{way}\:\mathrm{that}\:\mathrm{no}\:\mathrm{2}\:\mathrm{adjacent} \\ $$$$\mathrm{cells}\:\left(\mathrm{sharing}\:\mathrm{side}\right)\:\mathrm{have}\:\mathrm{the}\:\mathrm{same}\:\mathrm{color}.\:\mathrm{In}\:\mathrm{how} \\ $$$$\mathrm{many}\:\mathrm{ways}\:\mathrm{can}\:\mathrm{it}\:\mathrm{be}\:\mathrm{done}. \\ $$ Commented by 123456 last updated on 12/Apr/15…
Question Number 66262 by peter frank last updated on 11/Aug/19 $$\boldsymbol{{show}}\:\boldsymbol{{that}}\: \\ $$$$\:^{\boldsymbol{{n}}} \boldsymbol{{c}}_{\boldsymbol{{r}}+\mathrm{1}} +^{\boldsymbol{{n}}} \boldsymbol{{c}}_{\boldsymbol{{r}}\:\:} =^{\boldsymbol{{n}}+\mathrm{1}} \boldsymbol{{c}}_{\boldsymbol{{r}}+\mathrm{1}} \\ $$ Commented by mathmax by abdo…
Question Number 131744 by bemath last updated on 08/Feb/21 Answered by liberty last updated on 08/Feb/21 $$=\:\mathrm{C}_{\mathrm{3}} ^{\mathrm{7}} \:=\:\frac{\mathrm{7}.\mathrm{6}.\mathrm{5}}{\mathrm{3}.\mathrm{2}.\mathrm{1}}\:=\:\mathrm{35}\: \\ $$ Terms of Service Privacy…
Question Number 131635 by liberty last updated on 07/Feb/21 $$ \\ $$$$\mathrm{three}\:\mathrm{subject}\:\mathrm{group}\:\mathrm{are}\:\mathrm{to}\:\mathrm{be} \\ $$$$\mathrm{formed}\:\mathrm{randomly}\:\mathrm{by}\:\mathrm{15}\:\mathrm{students} \\ $$$$\left(\mathrm{including}\:\mathrm{3}\:\mathrm{girls}\right)\:\mathrm{under}\:\mathrm{the} \\ $$$$\mathrm{condition}\:\mathrm{that}\:\mathrm{each}\:\mathrm{groups} \\ $$$$\mathrm{consist}\:\mathrm{5}\:\mathrm{students}\:\mathrm{and}\:\mathrm{each} \\ $$$$\mathrm{student}\:\mathrm{attends}\:\mathrm{only}\:\mathrm{one}\:\mathrm{group}. \\ $$$$\mathrm{flnd}\:\mathrm{the}\:\mathrm{probabilities}\:\mathrm{that}\:\mathrm{of}\:\mathrm{the} \\…
Question Number 131553 by Salman_Abir last updated on 06/Feb/21 Answered by EDWIN88 last updated on 06/Feb/21 $$ \\ $$$$\mathrm{hahaha}\:….\:\mathrm{du}\:\mathrm{bist}\:\mathrm{groartig} \\ $$ Commented by Dwaipayan Shikari…