.........................................
I believe the answer to this is the third box
<span>Mean = 270
Standard deviation = 10
x = 255
Formula for z-score, z = (x - mean)/SD
z = (255 - 270) / 10
=> z = -15 / 10 => z = -1.5
So by referring to z-table, -1.5 correlates to 0.0668 that implies to 0.07
So 7% of the boxes of Apples weight less than 255oz.
The percentage of boxes is in the range of 255 oz and 270 oz,
Now calculating the requiring percentage 50% - 7% = 43%</span>
F(x)=x^2+bx-16
x=5
F(5)=5^2+b(5)-16
=25+5b-16=0
=5b+9=0
=5b=-9
=b= -9/5
By remainder theorem
You can divide 21 by 30 and that would give you 0.7 and if you divide 2 by 3 that would give you 0.6 repeating. Therefore, that is how I know that 21/30 is greater than 2/3.