In a class of 30 students, 9 have a brother and 17 have a sister. There are 7 students who have a brother and a sister. What is the probability that a student chosen randomly from the class has a brother and a sister?

What is the value of n in the equation -1/2(2n+4)+6=-9+4(2n+1)

Astudent must have an average on five test that is greater than it equal to 80% but less than 90% to receive a final grade of b. devon's greades on the first four test were 78% 62% 91% and 80% what range if grades on the fifth test would give him a b in the course? ( assuming the highest grade is 100%)

35 ! insert < , > , or = to make the sentence true. 12 __ 25 > =