1.
a) (12,2)=P(n,r)r!
c) C(n,r)=n(n-r)'r!
b) C(n,r)=C(1,1-r)
d) (m,n)=0
2. Which of the following situations involves combinations?
a) creating a pin for an ATM card
c) students falling in line
b) choosing first 6 volleyball players
d) making license plates
3. How many ways can a committee of 4 be formed with 10 people?
a) 180
c) 240
b) 210
d) 270
4. How many line segments can be drawn if there are 10 distinct non-collinear
on a plane?
a) 45
b) 15
c) 30
d) 50​