Question 705937

The general formula for number of subsets is {{{2^n}}} and the number of proper subsets is {{{2^n - 1}}}, where {{{n}}} is the number of elements.

if given set { .{{{15}}}, {{{10}}}, {{{16}}}, {{{20}}}, {{{19}}}.}, we can see that the number of elements is {{{n=5}}}

so, the number of subsets is 

{{{2^n=2^5=32}}} 

and the number of proper subsets is

{{{2^n - 1=2^5 - 1=32-1=31}}}