True! The absolute Value is just the value of the digit. -2+3=-1. The absolute value of -1 is 1. There is no other combination of numbers that would lead to this answer.
mean = (sum of values) / (number of values)
we know mean is 13 and we are given 8 values. The ninth value is the missing x:
13 = ((sum of 8 values) + x)/9
13 = (12+10+15+12+13+15+11+15+x)/9
13*9 = 103+x
x = 14
The missing value is 14. There are 14 pillows in the last box.
Just divide 100% by 80% and multiply that answer by 5. I'm pretty sure that's how you do it.
im not sure how to explain it, but i know its b