Six students in a social studies class will be divided into 3 pairs to

Question

Six students in a social studies class will be divided into 3 pairs to give presentations about the continents Africa, Asia and South America. Each pair will be assigned a different continent. How many complete assignments of the 6 students to the 3 continents are possible ?

(A) 15

(B) 20

(C) 36

(D) 64

(E) 90

(A) 15

(B) 20

(C) 36

(D) 64

(E) 90

Bunuel · Accepted Answer

pushpitkc · Answer

Since there are 6 students, and we need presentations about 3 continents
(Asia, Africa and South America) and a pair of students each to give these presentations.

For Asia, there would be  6c2(15)  ways of choosing the students 
For Africa, there would be  4c2(6)  ways of choosing the students
For South America, there would be  2c2(1)  way of choosing the students

Total ways possible of choosing the students is 15*6*1 =  90 ways(Option E)

Diablobuster · Answer

Number of different pairs of students: 6C2 = 15 pairs

Each pair can be assigned 3 countries = 45 different total assignments for pairs

Each pair has 2 students, so 2*45 = 90 total different assignments

bumpbot · Answer

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Six students in a social studies class will be divided into 3 pairs to

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