Sheet # 83 Critical Thinking

Name: _____________________ Date_____________

Arrange the set of numbers ( 1, 2, 3, 4) on the vertices of a square so that the sum of every pair of adjacent numbers is a prime number. In how many different combinations can this be done?

Answers for sheet # 83

There are 8 distinct ways. The even and odd numbers cannot be placed together around the square as that would not give you a primer number.

Combination # 1:

A= 1, B=2, C=3, D=4

(1,2,3,4)

Combination # 2

Exchange 2, and 4. New combination will be (1,4,3,2)

Combination # 3:

(4,1,2,3)

Combination # 4

(2,1,4,3)

Combination # 5

(3,4,1,2)

Combination # 6

(3, 2, 1 ,4)

Combination # 7

(2, 3, 4, 1)

Combination # 8

(4, 3, 2, 1)