1 votes 1 votes How many solutions do the following equations have? $x_1 + x_2 + x_3 =11$ where $x_1 \geq 1, x_2 \geq 2, x_3 \geq 3$ $C(7, 11)$ $C(11, 3)$ $C(14, 11)$ $C(7, 5)$ Discrete Mathematics ugcnetcse-dec2012-paper3 discrete-mathematics combinatory + – go_editor asked Jul 12, 2016 • recategorized Oct 10, 2018 by Pooja Khatri go_editor 1.1k views answer comment Share Follow See all 0 reply Please log in or register to add a comment.
Best answer 1 votes 1 votes It can be reduced as 11 similar balls into 3 different boxes... x>=1 , x2>=2, x3>=3 So 11 -(1+2+3) = 5 (remaining balls) It is combination with repetition... With 5 similar items and 3 different items... So ans is (5+3-1)C5 That is 7C5 papesh answered Jul 12, 2016 • selected Sep 16, 2016 by Sankaranarayanan P.N papesh comment Share Follow See all 0 reply Please log in or register to add a comment.
