To figure out the total, ignore the number of ours, but focus on the number of students. For the 5-7 hours section, there are about 25 students, since it's about 1/4 full to 40 from 20. How I figured this out is I looked at the difference of 40 and 20, which is 20, and saw 1/4 only filled, so there is 1/4 of 20 filled. 1/4 of 20 is 5, which means you add 5, leaving you 25. For the 8-10 hours section, there are about 130 students, as it is in the middle of 120 and 140. If you'd like to find out what's in the middle of two numbers, average them, meaning to sum them up and divide by how many numbers there are. For the 11-13 hours section, there's approximately 18. Now that we have our numbers, let's add up our total students. 25 + 130 + 18 = 173. The closest answer to 173 is 175. Your correct answer is B.) 175. I hope this helps!
