Posted by Anonymous on Saturday, April 23, 2011 at 12:59pm.
what is the proper subset for 13, 14, 15

math subsets  MathMate, Saturday, April 23, 2011 at 1:14pm
If A={13,14,15}
A proper subset B of A is such that
B∈A but B≠A.
The following sets are all proper subsets of A:
∅, {13}, {14}, {15}, {13,14}, {13,15}, {14,15}