Q15 of 118 Page 17

Mark the correct alternative in the following:

There are 10 points in a plane and 4 of them are collinear. The number of straight lines joining any two of them is


Number of straight lines formed by joining the 10 points if we take 2 points at a time = 10C2



Number of straight lines formed by joining the 4 points if we take 2 points at a time = 4C2



But, 4 collinear points, when joined in pairs give only one line.


Required number of straight lines =


45 – 6 + 1


= 40

More from this chapter

All 118 →
13

Mark the correct alternative in the following:

Three persons enter a railway compartment. If there are 5 seats vacant, in how many ways can they take these seats?


 14

Mark the correct alternative in the following:

In how many was can a committee of 5 be made out of 6 men and 4 women containing at least one women?


 16

Mark the correct alternative in the following:

There are 13 players of cricket, out of which 4 are bowlers. In how many ways a team eleven be selected from them so as to include at least two bowlers?


 17

Mark the correct alternative in the following:

If , then is equal to