Question

ln a class, there are 15 boys and 10 girls. Three students are selected at random. The probability that 1 girl and 2 boys are selected, is

पर्याय

• `21/46`

• `25/117`

• `1/50`

• `3/25`

Answer 1

`21/46`

Explanation:
Let S be the sample space and E be the event of selected 1 girl and 2 boys.
Then, n(S) = Number of ways selecting 3 students out of 25.

= `""^25C_3=((25xx24xx23))/((3xx2xx1))`

= 2300

n(E) = `(""^10C_1xx""^15C_2)`

= `[10xx((15xx14))/((2xx1))]= 1050`

∴ P E = `(n(E))/(n(S))=1050/2300=21/46`