In a boutique, a number of T-shirt are put on a stall for sale. The price and quantity for each type of T-shirt are listed below:
Price of each T-shirt...|$5 |$10|$15|$20|$30|$40
Number of T-shirt........|25 | 50 | 30 | 65 | 40 |40
If Winnie purchases 5 T-shirts randomly from the stall, what is the expected value of the amount she has to pay?
詳細steps plz~
F.3 Maths
2006-12-02 9:15 pm
回答 (2)
2006-12-02 9:54 pm
✔ 最佳答案
首先搵左一件的expected value先The average of 1 T-shirt:
$(5*25 + 10*50 + 15*30 + 20*65 + 30*40 + 40*40)÷(25 + 50 + 30 + 65 + 40 +40)
=$20.7
跟住就搵 5一件的expected value
The expected value of the amount she has to pay:
= $20.7*5
=$103.5
收錄日期: 2021-05-03 13:21:45
原文連結 [永久失效]:
https://hk.answers.yahoo.com/question/index?qid=20061202000051KK01858