# Combination Question I don’t understand

#### Snickey

##### New member
The answer for Q 15, C is 42. But I don’t know how to get it. Plz help

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#### pka

##### Elite Member
The answer for Q 15, C is 42. But I don’t know how to get it. Plz help
There are four classical CDs. So at least three means three or four.
He selects five. So include three or four classical and two or one other.
Look at this It seems 42 is incorrect.

#### Romsek

##### Full Member
I'm seeing the answer as 66 ways.

$$\displaystyle \dbinom{4}{3}\dbinom{6}{2}+\dbinom{4}{4}\dbinom{6}{1} = 66$$

I'm with Romsek.

#### Jomo

##### Elite Member
Yeah, pka and Romsek are correct.

#### Snickey

##### New member
Oh alright, I got the same answer too. Guess Cambridge got it wrong. Thanks everyone!