heightof three brothers

We set up equations. a+b+c=221, a=b+8, a=c+5

We have the equation a+b+c=221, and we understand that $b = a-8$ and $c= a-5$. Substituting b and c with their values in terms of a, we have $a + a - 8 + a - 5 = 221,$, which simplifies into $3a = 234$. Dividing both sides by 3, we have  $a = 78$ , so a's height is $\boxed{78}$ inches. 

If you wanted to know the height of b and c, we can revisit the equations b = a - 8 and c = a - 5. Simplifying b = 78 - 8, we know that b is 70 inches tall, and simplifying c = 78 - 5, we know that c is 73 inches tall. 

If you want to check your work, we can add 78, 70, and 73 to get 221, so our answers are correct.

Hope this helps, 

- PM