In a bin containing 30 parts, 27 parts are good and 3 parts are defective.
a) What is the probability that if you select 3 parts randomly, without replacing the parts in the bin, from the bin that you will have 1 defective part?
I thought of $\dfrac{\dbinom{27}{1}\dbinom{26}{1}\dbinom{3}{1}}{\dbinom{30}{1}\dbinom{29}{1}\dbinom{28}{1}}$