Question

if three straight line are drawn on a white board at random with the eyes closed show that the probability of forming a triangle is 1/7​

Answer 1

Answer:1/7

Step-by-step explanation:

S={(they form a single line i.e. they coincide each other),

(they form two parallel lines i.e. two lines coincide and parallel to  the other),

(they form two lines intersecting lines i.e. two lines coincide and intersect  with the other),                             (they form three lines intersecting at a point),(they form three lines which are parallel to each other),

(they form three lines among them two are parallel and the other one intersect them i.e. transversal),

(they form three lines and no two lines are parallel to one another i.e. they form a triangle)}                                

let E=event of getting forming a triangle  

 ={(they form three lines and no two lines are parallel to one another i.e. they form a triangle)}

so, P(E)=1/7.

Answer 2

Answer:

Step-by-step explanation:

Sample space

1. All three lines coincide

2. Two lines coincide and one parallel

3. All parallel

4.intersect at three distinct point

5. Two lines parallel and one intersect them

6.all pass through a point

7. Two lines coincide and one intersect.

So the total possible outcome is

7.

Favourable case is 1.

So the probability is 1/7