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diff --git a/2294/CH12/EX12.5/EX12_5.sce b/2294/CH12/EX12.5/EX12_5.sce
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+//Example 12.5
+//Probability to find the first white ball on the 3rd draw.
+disp('Let A be the event of drawing the first white ball at the third draw from 15 balls ')
+disp('Let W be the event of drawing a 10 white balls')
+disp('Let B be the event of drawing a 5 black balls')
+disp('Hence we have 1st draw :B  2nd Draw :B  3rd Draw :W');
+funcprot(0)
+function c = combination ( n , r )
+c = prod ( n : -1 : n-r+1 )/ prod (1:r)
+endfunction
+disp('P(A)={(5 C 1)*(5 C 1)*(10 C 1)}/{(15 C 1)*(15 C 1)*(15 C 1)}=')
+p=(combination(5,1)*combination(5,1)*combination(10,1))/(combination(15,1)*combination(15,1)*combination(15,1))
+disp(p)