topic Re: Reg: Probability in SAS Programming https://communities.sas.com/t5/SAS-Programming/Reg-Probability/m-p/38900#M7868 <HTML><HEAD></HEAD><BODY><P>I am not sure if this is the right place for you to ask this kind of question, unless you were asking how to calculate it using SAS, which in that case, I can't provide the answer. That being said, you may get better answers(academic wise) elsewhere.</P><P></P><P>Q1. </P><P>&nbsp;&nbsp;&nbsp; When you say 'chance', I would reflect 'probability', which will never larger than 1 (I hope I am not too statistical anal here). Anyway, to anwer your question:</P><P>If you throw 3 times, then the total number of possible senario will be: 2(head,tail)*2*2=8</P><P>And the total number of 2-heads secario: 3*2/2=3, sorry don't know how to post the formula symbol.</P><P>Therefore the chance of your getting 2-heads is 3/8.</P><P></P><P></P><P>Q2.</P><P>Can't believe they ask that in an interview. Anyway, the maxium time you need to weigh is 3. here is how:</P><P>Rondomly you picked 4 balls, one pair on each side of balance:</P><P></P><P>pair A vs. Pair B,</P><P>1. if they don't balance, then choose the lighter pair do another weighing, then you get your answer. This is the better scenario, which only takes 2 times.</P><P>2. if they do balance, then put them aside, choose another 2 pairs from remaining 5 balls, and weight</P><P>&nbsp;&nbsp;&nbsp; 2.1&nbsp; if they do balance, then you will know the unweighed left one is the culprit. 2 times.</P><P>&nbsp;&nbsp;&nbsp; 2.2&nbsp; if they don't balance, then it will take you another weighing to decide. This is the worst scenario, and it takes 3 times.</P><P></P><P></P><P>Regards,</P><P>Haikuo</P></BODY></HTML> Wed, 21 Mar 2012 12:37:45 GMT Haikuo 2012-03-21T12:37:45Z Reg: Probability https://communities.sas.com/t5/SAS-Programming/Reg-Probability/m-p/38899#M7867 <HTML><HEAD></HEAD><BODY><P><BR />Actually i am having a Query for probability asked in a Interview</P><P></P><P>Q:1</P><P>&nbsp; If i have tossed a coin for 3 times what is the chance of getting Head 2 Times</P><P>they told 2 times but how.Can any one explain.</P><P><BR />Q:2</P><P>I am having 9 balls out of which i am having one ball with less weight each ball weight is 1 kg and the defect ball has 1 gm les in weight.<BR />&nbsp; I am having a balance at once 2 balls can we weighed in two pans.</P><P>What is the probaility to find the defect ball </P><P>The answer is 3 But how.</P></BODY></HTML> Wed, 21 Mar 2012 11:58:49 GMT https://communities.sas.com/t5/SAS-Programming/Reg-Probability/m-p/38899#M7867 sas_Forum 2012-03-21T11:58:49Z Re: Reg: Probability https://communities.sas.com/t5/SAS-Programming/Reg-Probability/m-p/38900#M7868 <HTML><HEAD></HEAD><BODY><P>I am not sure if this is the right place for you to ask this kind of question, unless you were asking how to calculate it using SAS, which in that case, I can't provide the answer. That being said, you may get better answers(academic wise) elsewhere.</P><P></P><P>Q1. </P><P>&nbsp;&nbsp;&nbsp; When you say 'chance', I would reflect 'probability', which will never larger than 1 (I hope I am not too statistical anal here). Anyway, to anwer your question:</P><P>If you throw 3 times, then the total number of possible senario will be: 2(head,tail)*2*2=8</P><P>And the total number of 2-heads secario: 3*2/2=3, sorry don't know how to post the formula symbol.</P><P>Therefore the chance of your getting 2-heads is 3/8.</P><P></P><P></P><P>Q2.</P><P>Can't believe they ask that in an interview. Anyway, the maxium time you need to weigh is 3. here is how:</P><P>Rondomly you picked 4 balls, one pair on each side of balance:</P><P></P><P>pair A vs. Pair B,</P><P>1. if they don't balance, then choose the lighter pair do another weighing, then you get your answer. This is the better scenario, which only takes 2 times.</P><P>2. if they do balance, then put them aside, choose another 2 pairs from remaining 5 balls, and weight</P><P>&nbsp;&nbsp;&nbsp; 2.1&nbsp; if they do balance, then you will know the unweighed left one is the culprit. 2 times.</P><P>&nbsp;&nbsp;&nbsp; 2.2&nbsp; if they don't balance, then it will take you another weighing to decide. This is the worst scenario, and it takes 3 times.</P><P></P><P></P><P>Regards,</P><P>Haikuo</P></BODY></HTML> Wed, 21 Mar 2012 12:37:45 GMT https://communities.sas.com/t5/SAS-Programming/Reg-Probability/m-p/38900#M7868 Haikuo 2012-03-21T12:37:45Z