### Sets

goals
In a group of 15 people, 7 read French, 8 read English while 3 of them read none of them. How many read French and English both?
Find the number of subsets of a set whose set contains $6$ elements.
If $A=\left\{ 1,\cfrac { 1 }{ 4 } ,\cfrac { 1 }{ 9 } ,\cfrac { 1 }{ 16 } ,\cfrac { 1 }{ 25 } \right\}$, then write $A$ in Set-builder form.
Let  $A , B$  be two set such that  $n ( A ) = 4$  and  $n ( B ) = 6$  then the least possible number of elements in the power set  of  $( A \cup B )$  is
Write two sets each involving algebraic and geometrical ideas .