Respuesta :
Answer:
(A)Therefore the number of dish of three scoops of ice cream is 4,060.
(B)The different kinds of sundaes are 2668.
(C) Therefore total numbers of different sundaes are 25,009,600.
Step-by-step explanation:
- Definition of permutation:
The order of event is counted.
1. Repetition not allowed: P(n,r) [tex]=\frac{n!}{(n-r)!}[/tex]
2. Repetition allowed: [tex]n^r[/tex]
- Definition of combination
The order of event is not counted.
1. Repetition not allowed:
[tex]C(n,r) =\left(\begin{array}{ccc}n\\r\end{array}\right)=\frac{n!}{r!(n-r)!}[/tex]
2. Repetition allowed:
[tex]C(n+r-1,r) =\left(\begin{array}{ccc}n+r-1\\r\end{array}\right)=\frac{(n+r-1)!}{r!(n-1)!}[/tex]
(A)
The order of scope does not matter and repetition allowed. So we use the second formula of combination.
The scoops are then 3 section from 28 different flavors
n=28
r=3
[tex]\therefore C(28+3-1,3) =\left(\begin{array}{c}30\\3\end{array}\right)=\frac{(30)!}{3!27!}=4,060[/tex]
Therefore the number of dish of three scoops of ice cream is 4,060.
(B)
Given a small sundae contains one scoop of ice cream, a sauce and a topping.
The different kinds of sundaes are C(28,1)×C(8,1)×C(12,1)
=28×8×12
=2688
(C)
Scoop:
The order of the scoop does not matter and repetition is allowed.
So, we use the definition of combination of repetition.
n=28
r=3
[tex]C(28+3-1,3)=C(30,3)=\frac{30!}{3!27!}=4060[/tex]
Sauce:
The order of the sauce does not matter and repetition is not allowed.
So, we use the definition of combination of repetition is not allowed.
n=8
r=2
[tex]C(8,2)=\frac{8!}{2!(8-2)!}=\frac{8!}{2!6!}=28[/tex]
Topping:
The order of the topping does not matter and repetition is not allowed.
So, we use the definition of combination of repetition is not allowed.
n=12
r=3
[tex]C(12,3)=\frac{12!}{3!(12-3)!}=\frac{12!}{3!9!}=220[/tex]
Therefore total number of different sundaes are = (4060×28×220)
=25,009,600