SOLUTION: Let A= { 15,16,17,18,19,20} How many subsets does A have? How many proper subsets does A have?

Question 912435: Let A= { 15,16,17,18,19,20} How many subsets does A have? How many proper subsets does A have?
Answer by MathLover1(20850) (Show Source): You can put this solution on YOUR website!

A complete list of the subsets of A= { 15,16,17,18,19,20} is:
there are subsets and proper subsets

{},{15},{16},{17},{18},{19},{20},{15,16},{15,17},{15,18},{15,19},{15,20},{16,17},{16,18},{16,19},{16,20},{17,18},{17,19},{17,20},{18,19},{18,20},{19,20},{15,16,17},{15,16,18},{15,16,19},{15,16,20},{15,17,18},{15,17,19},{15,17,20},{15,18,19},{15,18,20},{15,19,20},{16,17,18},{16,17,19},{16,17,20},{16,18,19},{16,18,20},{16,19,20},{17,18,19},{17,18,20},{17,19,20},{18,19,20},{15,16,17,18},{15,16,17,19},{15,16,17,20},{15,16,18,19},{15,16,18,20},{15,16,19,20},{15,17,18,19},{15,17,18,20},{15,17,19,20},{15,18,19,20},{16,17,18,19},{16,17,18,20},{16,17,19,20},{16,18,19,20},{17,18,19,20},{15,16,17,18,19},{15,16,17,18,20},{15,16,17,19,20},{15,16,18,19,20},{15,17,18,19,20},{16,17,18,19,20},{15,16,17,18,19,20}
All of these are proper subsets of { 15,16,17,18,19,20} except for { 15,16,17,18,19,20} itself.
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