Question Number 199270 by mr W last updated on 31/Oct/23 Commented by mr W last updated on 31/Oct/23 $${an}\:{unsolved}\:{old}\:{question}\:#\mathrm{199155}. \\ $$ Commented by mr W…
Question Number 199031 by cortano12 last updated on 27/Oct/23 Commented by AST last updated on 27/Oct/23 $${For}\:\mathrm{4},\:{are}\:{the}\:{English}\:{or}\:{Mathematics}\:{books} \\ $$$${all}\:{different}? \\ $$ Answered by mr W…
Question Number 199054 by cortano12 last updated on 27/Oct/23 $$\:\:\boldsymbol{{x}} \\ $$ Answered by AST last updated on 27/Oct/23 $$\left(\mathrm{1}+{x}\right)\left(\mathrm{2}+{x}^{\mathrm{2}} \right)\left(\mathrm{3}+{x}^{\mathrm{3}} \right)\left(\mathrm{4}+{x}^{\mathrm{4}} \right)\left(\mathrm{5}+{x}^{\mathrm{5}} \right)\left(\mathrm{6}+{x}^{\mathrm{6}} \right)…
Question Number 198851 by Tawa11 last updated on 25/Oct/23 You want to arrange 17 books on the shelf of a bookstore. The shelf is dedicated…
Question Number 198809 by dimentri last updated on 24/Oct/23 $$\:\:\:\:\:{sum}\:{of}\:{roots}\: \\ $$$$\:\mathrm{log}\:_{\mathrm{3}} {x}\:+\:\mathrm{log}\:_{\mathrm{3}} \left(\mathrm{2},\mathrm{5}\right)\:+\:\mathrm{log}\:_{{x}} \mathrm{9}\:=\:\mathrm{3}+\:\mathrm{log}\:_{{x}} \mathrm{5}\: \\ $$ Answered by a.lgnaoui last updated on 24/Oct/23…
Question Number 198576 by mr W last updated on 22/Oct/23 How many numbers with a maximum of 5 digits, greater than 4000, can be formed…
Question Number 198548 by HomeAlone last updated on 21/Oct/23 $${return}\mathrm{return}\left(\right) \\ $$$$\mathrm{p}<\mathrm{1} \\ $$$$\mathrm{p} \\ $$$$\mathrm{2} \\ $$$$\mathrm{3} \\ $$$$\mathrm{4} \\ $$$$\mathrm{5} \\ $$$$\mathrm{6} \\…
Question Number 198283 by cortano12 last updated on 16/Oct/23 $$\mathrm{Given}\:\mathrm{the}\:\mathrm{number}\:\mathrm{of}\:\:\mathrm{consisting} \\ $$$$\:\mathrm{of}\:\mathrm{4}\:\mathrm{digits}\:\mathrm{abcd}\:\mathrm{such}\:\mathrm{that}\: \\ $$$$\:\mathrm{a}\leqslant\mathrm{b}\leqslant\mathrm{c}\leqslant\mathrm{d}\:\mathrm{is}\:… \\ $$$$\:\left(\mathrm{A}\right)\:\mathrm{495}\:\:\:\left(\mathrm{B}\right)\:\mathrm{385}\:\:\:\:\:\left(\mathrm{C}\right)\:\mathrm{275} \\ $$$$\:\left(\mathrm{D}\right)\:\mathrm{165}\:\:\:\:\left(\mathrm{E}\right)\:\mathrm{55}\: \\ $$ Commented by mr W last…
Question Number 198242 by Tawa11 last updated on 15/Oct/23 How many numbers with a maximum of 5 digits, greater than 4000, can be formed with…
Question Number 198231 by pticantor last updated on 14/Oct/23 Answered by witcher3 last updated on 14/Oct/23 $$\mathrm{C}_{\mathrm{n}} ^{\mathrm{p}} =\frac{\mathrm{n}!}{\mathrm{p}!.\left(\mathrm{n}−\mathrm{p}\right)!} \\ $$$$\mathrm{pC}_{\mathrm{n}} ^{\mathrm{p}} =\frac{\mathrm{n}!}{\left(\mathrm{p}−\mathrm{1}\right)!.\left(\mathrm{n}−\mathrm{p}\right)!}=\mathrm{n}.\frac{\left(\mathrm{n}−\mathrm{1}\right)!}{\left(\mathrm{p}−\mathrm{1}\right)!.\left(\mathrm{n}−\mathrm{1}−\left(\mathrm{p}−\mathrm{1}\right)\right)!} \\ $$$$=\mathrm{nC}_{\mathrm{n}−\mathrm{1}}…