Answer:
e=-7
Step-by-step explanation:
Answer:
2.275%
Step-by-step explanation:
The first thing to do here is to calculate the z-score
Mathematically;
z-score = (x-mean)/SD
from the question, x = 12,300 hours , mean = 11,500 hours while Standard deviation(SD) = 400 hours
Plugging the values we have;
z-score = (12,300-11,500)/400 = 800/400 = 2
Now, we want to calculate P(z ≤ 2)
This is so because we are calculating within a particular value
To calculate this, we use the z-score table.
Mathematically;
P(z ≤ 2) = 1 - P(z > 2) = 1 - 0.97725 = 0.02275
To percentage = 2.275%
<span>d=drinks
p=pretzels
1st eq. 3d+3p=9.00
2nd eq. 4d+2p=8.50</span>
multiply
1st eq by 2
6d+6p=18.00
<span>multiply
2nd eq by 3
12d+6p=25.50
subtract
-6d=-7.50
d=1.25
3p=9.00-3d</span>
3p=9-3.75
<span>3p=5.25
p=1.75
price of a pretzel=$1.75</span>
<span> price of a drink = $1.25</span>