Expression 3: "y" equals Start sum from "n" equals 0 to "x" minus 1, end sum, .3 3 7 times StartFraction, nCr left parenthesis, 40 minus "x" , 5 , right parenthesis Over nCr left parenthesis, 40 , 5 , right parenthesis , EndFraction times StartFraction, nCr left parenthesis, "x" , "n" , right parenthesis times nCr left parenthesis, 35 minus "x" , 10 minus "n" , right parenthesis Over nCr left parenthesis, 35 , 10 , right parenthesis , EndFraction times left parenthesis, 1 minus StartFraction, nCr left parenthesis, 25 minus left parenthesis, "x" minus "n" , right parenthesis , 2 , right parenthesis Over nCr left parenthesis, 25 , 2 , right parenthesis , EndFraction , right parenthesisy=x−1∑n=0.337·nCr40−x,5nCr40,5·nCrx,n·nCr35−x,10−nnCr35,10·1−nCr25−x−n,2nCr25,2
3
"x"x
Start sum from "n" equals 0 to "x" minus 1, end sum, .3 3 7 times StartFraction, nCr left parenthesis, 40 minus "x" , 5 , right parenthesis Over nCr left parenthesis, 40 , 5 , right parenthesis , EndFraction times StartFraction, nCr left parenthesis, "x" , "n" , right parenthesis times nCr left parenthesis, 35 minus "x" , 10 minus "n" , right parenthesis Over nCr left parenthesis, 35 , 10 , right parenthesis , EndFraction times left parenthesis, 1 minus StartFraction, nCr left parenthesis, 25 minus left parenthesis, "x" minus "n" , right parenthesis , 2 , right parenthesis Over nCr left parenthesis, 25 , 2 , right parenthesis , EndFraction , right parenthesisx−1∑n=0.337·nCr40−x,5nCr40,5·nCrx,n·nCr35−x,10−nnCr35,10·1−nCr25−x−n,2nCr25,2