math. problems

Q1

For supplementary angles, their sum = 180

Since ratio of the 2 angles
= 3 : 6
= 1 : 2

Let the smaller angle = y and the greater angle = 2y
So
y + 2y = 180
3y = 180
y = 60

So, the measure of the smaller angle = 60 The answer is (4)

Q3

For randomly select 3 freshmen from 9, number of ways = 9C3

For randomly select 2 sophomores from 7, number of ways = 7C2

Number of different committees can be formed
= 9C3 x 7C2
=1764

The answer is (2)

very ezzy......