contestada

You are required to choose two topics from a list of five to write about on your science test. How many different pairings are possible?

Respuesta :

A B C D E represent the subjects


A+A1

A+B2

A+C3

A+D4

A+E5

B+B6

B+C7

B+D8

B+E9

C+C10

C+D11

C+E12

D+D13

D+E14

E+E15

15 combos
There are many 20 different pairings possible.