If you would like to know how many papers will be missing the name, you can calculate this using the following steps:
30% of 200 homework papers = 30% * 200 = 30/100 * 200 = 60 homework papers
The correct result would be a) between 50 and 70 papers will be missing the name.
S= number of small boxes
l= number of large boxes
equation 1: s+l=120
equation 2: 15s+45l=3300
solve by elimination, multiply equation 1 by -15.
-15(s+l=120) = -15s-15l=-1800 add to equation 2.
-15s+15s-15l+45l=-1800+3300 = 30l=1500
30l=1500 , l=50
s+l=120, s+50=120 --> s=70
I have a photo that shows how I got the answer and what the answer is (Key: Red represents my work, while highlighter shows what the answer is):
