Alright, so the sum of two days is going to equal zero.
The variable here is what Jesse got on the first day. Let's call it "x".
x-6=0
x is the first day's score, -6 is the second day's score, and the total score is zero.
Now, add 6 to both sides.
x-6=0
+6 +6
x=6
Jesse's score for the first day was (+)6.
I think maybe the answer is probably 7. Hope this helps !!
Roughly 1.7 percent of the bands are shorter than 3cm. We calculate the z score of the data point in standard distribution. By definition of z score, we use score minus mean divided by standard deviation. z=(3-6)/1.5=-2. A z score of -2 corresponds to approximately 1.7%, in other words, roughly 1.7 percent of data is less than 3cm.