How is 5 1/2inches the same as 11 half inches?

Well you add 1/2 + 1/2 = 1 in

(1/2+1/2) + (1/2+1/2) + (1/2+1/2) + (1/2+1/2) + (1/2+1/2) + 1/2=

2 half inches per parentheses pairs which is 5 plus the 1/2 inch

(11 half inches shown above)

If you must, try writing the fraction (1/2) eleven times and then write the addition operator (" + ") between each such fraction: (1/2) + (1/2) + ... + (1/2) + (1/2). You'll see that adding 11 of these fractions (1/2) together produces a sum of 5 1/2.