Question

Can someone please answer. There is one problem. There's a picture. Thank you!

Answer 1

In how many ways to choose: C = Combination

2 CDs from 3 CDs = ³C₂ = (3*2)/(2*1) = 3

4 Cassettes from 4 = ⁴C₄ = (4*3*2*1)/(4*3*2*1) = 1

2 DVDs from 5 = ⁵C₂ = (5*4)/(2*1) = 10

Total = 3 * 1 * 10 = 30

Answer 2

`\displaystyle \binom{3}{2}\cdot\binom{4}{4}\cdot \binom{5}{2}= (3!)/(2!1!)\cdot1\cdot(5!)/(2!3!)=3\cdot1\cdot10=30 \Rightarrow D`