Permutation and Combination Questions

Question Number 105853 by bobhans last updated on 01/Aug/20

$${A}\:{box}\:{contains}\:\mathrm{5}\:{balls},\:\mathrm{2}\:{balls}\:{were} \\$$$${drawn}\:{at}\:{random},\:{both}\:{of}\:{which} \\$$$${turned}\:{out}\:{tobe}\:{white}.\:{what}\:{is}\:{the} \\$$$${probability}\:{that}\:{all}\:{the}\:{balls}\:{in}\:{the}\:{box} \\$$$${are}\:{white}\:? \\$$

Commented by bobhans last updated on 01/Aug/20

$${thank}\:{you}\:{sir} \\$$

Commented by PRITHWISH SEN 2 last updated on 01/Aug/20

$$\mathrm{Is}\:\mathrm{the}\:\mathrm{question}\:\mathrm{ok}\:? \\$$

Commented by bobhans last updated on 01/Aug/20

$${in}\:{my}\:{book}\:{is}\:{ok} \\$$

Commented by mr W last updated on 01/Aug/20

$${i}\:{don}'{t}\:{the}\:{question}\:{is}\:{ok}.\:{are}\:{the}\:{balls} \\$$$${of}\:{only}\:{two}\:{colors}\:{or}\:{of}\:{three}\:{colors} \\$$$${or}\:{even}\:{more}? \\$$

Commented by mr W last updated on 01/Aug/20

$${supposed}\:{the}\:{balls}\:{are}\:{white}\:{or}\:{black}. \\$$$${the}\:{remaining}\:{three}\:{balls}\:{could}\:{be}: \\$$$${BBB} \\$$$${BBW} \\$$$${BWW} \\$$$${WWW} \\$$$${so}\:{the}\:{possiblity}\:{that}\:{all}\:{balls}\:{are}\:{write} \\$$$${is}\:\frac{\mathrm{1}}{\mathrm{4}}. \\$$