How to determine the speed of GLUT1 transporter using Michaelis-Menten kinetics?

I am reviewing a passage in my Lehninger Biochemistry Textbook (6th Edition), and the following passage has me very confused.


How can one sentence from this passage claim that when [S]out = Kt, the rate of uptake is 1/2 Vmax, but then go on to say that when the concentration in the blood is *close* to Kt that GLUT1 operates near Vmax?


[![enter image description here](https://i.stack.imgur.com/rrqNf.png)](https://i.stack.imgur.com/rrqNf.png)


