Question

find the number of non negative interger solution with system of equantion a+b+c+d+e =20 and a+b+b = 5

Answer 1

​  

c  

15

​  

=  

16

​  

c  

15

​  

 

So, required numbers =  

16

​  

c  

15

​  

×  

7

​  

c  

5

​  

=336