In a particular lottery, 3 million tickets are sold each week for 50 美金.
Out of the 3 million tickets, 12006 are drawn at random and without replacement
and awarded prizes : twelve thousand $25 prized, four $10000 prizes,
one $50000 prizes,and one $200000 prize. If you purchased a single ticket
each week, what is the expected value of this game to you ?
答案是:
25x(12000/3000000) + 10000(4/3000000) + 50000(1/3000000)+
200000(1/3000000) - 50/100
那麼我想問的是為何最後要減去 50/100 ?!?!
拜託高手幫幫忙!!
更新1:
喔喔 因為題目是50¢ piece ...一開始不知道怎麼打出50後面那個c一撇的東西!! 所以這代表是什麼意思@@?美分!?!
更新2:
喔喔喔~我懂了!!所以那是50美分=0.5美金囉?!哇!!題目看不懂會很慘T_T~!!
