Today’s SAT Question of the Day is a math question about counting.  These simplistic questions often contain more than meets the eye – and this one is testing your knowledge of a simple rule of counting.

On the last day of a one-week sale, customers numbered 149 through 201 were waited on. How many customers were waited on that day?

I bet most of you just subtracted 149 from 201, bubbled in 52, and moved on.  But what if I told you that isn’t the answer?Let’s start with some smaller numbers to see why the answer isn’t 52 – and find out the correct answer.  For my example, I’m going to use customers 9 through 11. This number line shows customers 9 through 11….

Three purple dots mean 3 customers: we waited on #9, #10, and #11.  Another way to look at is is that we waited on 11 – 9 + 1 customers.  Either of these methods will help you get a correct answer on test day.

Back to our question – how many customers are there from 149 through 201?

201 – 149 + 1 = 53