从1~5五个整数中随机取3个,以X表示3个数中的最大值.X的可能值为3,4,5.在五个数中任取3个共有(C53=10种取法.
{X=3}表示取出的3个数以3为最大值.其余两数只能是1,2,仅有这一种情况,故
{X=4}表示取出的3个数以4为最大值,其余两个数交互1,2,3中任取2个,共有C32=3种取法,
{X=5}表示取出的3个数以5为最大值,其余两个数从1,2,3,4中任取2个,共有C42=6种取法,故,P{X=5}也可由1-P{X=3}-P{X=4}得到
因此X的分布律为
X 3 4 5
pk frac{1}{10} frac{3}{10} frac{6}{10}
追问少三张图片,
追答![](https://video.ask-data.xyz/img.php?b=https://iknow-pic.cdn.bcebos.com/6d81800a19d8bc3e9aba49478a8ba61ea9d34588?x-bce-process=image%2Fresize%2Cm_lfit%2Cw_600%2Ch_800%2Climit_1%2Fquality%2Cq_85%2Fformat%2Cf_auto)
![](https://video.ask-data.xyz/img.php?b=https://iknow-pic.cdn.bcebos.com/5243fbf2b21193135389b03d6d380cd790238d71?x-bce-process=image%2Fresize%2Cm_lfit%2Cw_600%2Ch_800%2Climit_1%2Fquality%2Cq_85%2Fformat%2Cf_auto)
![](https://video.ask-data.xyz/img.php?b=https://iknow-pic.cdn.bcebos.com/08f790529822720eb162ad7773cb0a46f31fab8b?x-bce-process=image%2Fresize%2Cm_lfit%2Cw_600%2Ch_800%2Climit_1%2Fquality%2Cq_85%2Fformat%2Cf_auto)
符号打不出来,所以借用人家图片了,将
换成X
追问图片看不清啊。。
追答![](https://video.ask-data.xyz/img.php?b=https://iknow-pic.cdn.bcebos.com/6d81800a19d8bc3eaef5b5478a8ba61ea9d345b9?x-bce-process=image%2Fresize%2Cm_lfit%2Cw_600%2Ch_800%2Climit_1%2Fquality%2Cq_85%2Fformat%2Cf_auto)