



 
Hi Shipra, If the candidate fails more papers than he passes and there are 9 papers, this mean he would be unsuccessful if he fails 5 or more papers. So in other words he could fail 5 out of 9 papers, 6 out of 9 papers, 7 out of 9 papers, 8 out of 9 papers or all 9 papers to be unsuccessful. For each scenario, there are many different combinations of papers to pass or fail. To put it into mathematical terms if he failed 5 papers out of 9 _{9}C_{5} = 126 There are 126 different ways to fail 5 papers out of a group of 9. Once you figure out how many combinations are for each unsuccessful scenario, add all of the scenarios together to find the total. Hope this helps, Janice
 


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