1.An unlimited number of red, white, blue and green balls are given. The number of ways of
selecting 10 balls is ?
2.The greatest possible number of points of intersection of 8 straight lines and 4 circles is?
11Ans 2) 8 straight lines intersects each other in 8 C 2 ways = 28 points
4 circles intersects each other in 4 P 2 ways = 12 points
Now, every line cuts 4 circles into 8 points. Therefore, 8 st liines will cut 4 circles into 64 points.
Therefore, the max no. of points = 28 + 12 + 64 = 104 points
1the first ques. is same as answerin the no. of solns to x + y + z +x + w = 10 , all >=0
