Question

Mark four points P, Q, R and S such that no
three points lie on a straight line. How many
triangles can be formed by joining them ?
Name them (using P, Q, R, S, only).​

Answer 1

Answer:

4 triangles namely PQR, QRS, RSP, SPQ

Step-by-step explanation:

We need 3 points to make a triangle, and the order of choice wouldn't matter.

Here we'll use permutation.

So, number of triangles = nPr = 4P3 = 4!/3! = 24/6 = 4