Answer:
if 1/6 of a roll of paper covers 1/4 of a wall, this means that we will need 4/6 of a roll to cover a whole wall, now the question is asking how many rolls will we need to cover 4 walls, we already know that it takes 4/6 to fill one wall so if we add 4/6+4/6+4/6+4/6 we will get 16/6 or 2 4/6
we will need 16/6 or 2 4/6 of rolls of paper to cover 4 walls
The answer is x= -5 ...explained... -2x + 5 -35x= 190...-37x +5 = 190 ... now subtract 190-5 = 185... divide 185 by - 37 and get -5
75/25 = 3
3x25 = 75
$25 per hour
You're looking for a value

such that

Because the distribution is symmetric, the value of

in either case will be the same.
Now, because the distribution is continuous, you have that

The mean for the standard normal distribution is

, and because the distribution is symmetric about its mean, it follows that

.

You can consult a

score table to find the corresponding score for this probability. It turns out to be

.