Question

If a computer network has 60 switching nodes, in how many ways can 2 or 3 nodes fail?___________

Answer 1

Answer:

There are 35990 ways in which 2 or 3 nodes fail

Step-by-step explanation:

Given : A computer network has 60 switching nodes.

To Find : In how many ways can 2 or 3 nodes fail?

Solution:

We are supposed to find no. of ways can 2 or 3 nodes fail.

So, we will use combination here .

No. of ways can 2 or 3 nodes fail=$^{60}{C_2 +^{60}C_3$

Formula : $^nC_r =\frac{n!}{r!(n-r)!}$

No. of ways can 2 or 3 nodes fail=$\frac{60!}{2!(60-2)!}+\frac{60!}{3!(60-3)!}$

                                                       =$35990$

Hence there are 35990 ways in which 2 or 3 nodes fail