Submitted by FletchOnMaths on Thu, 07/27/2017 - 17:14
At the very bottom of page 1 of the feedback https://maths.org/step/sites/maths.org.step/files/Feedback_A7_0.pdf , for
$ \frac 12 \le x<0$
read
$ - \frac 12 \le x<0$
Either that, or I completely fluffed this warm-up question. :-)
Thanks!
Fixed now (and hopefully no new errors introduced!)