a)Number of boarders= 350 students
Number of non-boarder = 630-350=280 students.
Probability that the student is a boarder is 350 out of 630
P(B)=350/630=5/9
b).No. of girls in the school= 4/7 x 630 =270
No.of boys in the school = 4/7 x 630 = 360
Probability that the student is a girl is 270 out of 630
P(B)= 280/630
= 4/9
Probability of girl and not a boarder
= 3/7 x 4/9
= 4/21
Githiari answered the question on April 3, 2019 at 17:25
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