What is 1 lb 4 oz plus 1 lb 2 oz equal?

[ 11 lb + 12 oz ] + [ 6 lb + 6 oz ] =

[ 11 lb + 6 lb ] + [ 12 oz + 6 oz ] =

[ 17 lb ] + [ 18 oz ] =

[ 17 lb ] + [ 1 lb + 2 oz ] =

18 lb 2 oz