Answer: [tex]\dfrac{60}{143}[/tex]
Step-by-step explanation:
Given, A class has five boys and nine girls.
Total students = 5+9=14
Number of ways to choose 6 students out of 14= [tex]^{14}C_6[/tex] [Using combinations]
Number of ways to choose 4 girls out of 6 (4 girls + 2 boys = 6 ) = [tex]^{9}C_4\times\ ^{5}C_2[/tex]
If the teacher randomly picks six students, then the probability that he will pick exactly four girls:-
[tex]\dfrac{^{9}C_4\times \ ^{5}C_2}{^{14}C_6}[/tex]
[tex]=\dfrac{\dfrac{9!}{4!5!}\times\dfrac{5!}{2!3!}}{\dfrac{14!}{6!8!}}\\\\=\dfrac{1260}{3003}\\\\=\dfrac{60}{143}[/tex]
hence, the required probability = [tex]\dfrac{60}{143}[/tex] .
