Question

B={a?a?Nand61<a<86}B={a?a??and61<a<86}

BB has subsets.

BB has proper subsets

Answer 1

Given, the set B = {a?a?N and 61<a<86}

So, this set is of natural numbers greater than 61 and less than 86.

B = {62,63,64,65,66,67,68,69,.....85}

Now, Subset: A set of elements which are in B or B itself.

So, some subsets: {62}, {62,67}, {67,68,69,77} and {62,63,64,65,66,67,68,69,.....85} etc.

Now, Proper subset: A set of elements which are in B but not entire B.

So, {62,63,64,65,66,67,68,69,.....85} is NOT a proper subset and except this, all are proper subsets.

Eg: {62}, {62,67}, {67,68,69,77