If the probability of Sita getting selected to a school is 20% and she applied to 3 schools. What is the probability that she will get selected in at least one school?  Choose the correct choice
A) 24/125	B) 21/125	C) 61/125	D) 12/125	E) 18/125
The probability that she will be selected by at least one school equals to the sum of the probabilities of the following three events:   1. She is selected by only one school: P(SRR)=3!/2!∗1/5∗4/5∗4/5=48/125 (S stands for selected and R stands for rejected). We are multiplying by 3!/2! since SRR scenario can occur in several ways: SRR, RSR, RRS, (so 3!/2! is # of permutations of 3 letters SRR out of which 2 R's are identical);   2. She is selected by only two school: P(SSR)=3!/2!∗1/5∗1/5∗4/5=12/125, the same reason of multiplying by 3!/2!;   3. She is selected by all three school: P(SSS)=(15)^3=1125, we are not multiplying this time since SSS can occur only in one way.   So P=48/125+12/125+1/125=61/125   Answer: 61/125
<result>C</result>
If the probability of Sita getting selected to a school is 20% and she applied to 3 schools. What is the probability that she will get selected in at least one school?