Answer:
The cost is;
$18.43
Step-by-step explanation:
The general model for a linear equation is;
y = mx + b
let y be the monthly cost in dollars
x is the number of minutes
b will represent the base cost
m is the cost of the call per minute
so let us get m and b
Thus, we have;
18.25 = 31m + b
19.42 = 44m + b
Subtract i from ii
(19.42-18.25) = (44-31)m
1.17 = 13m
m = 1.17/13 = 0.09
To get b, we substitute the value of m in any of the equation
18.25 = 31 m + b
18.25 = 31(0.09) + b
b = 18.25 - 2.79
b = 15.46
so, the equation of the line is;
y = 0.09x + 15.46
Now to get the cost for 33 minutes
simply substitute the value of 33 for x
we have this as;
y = 0.09(33) + 15.46
y = $18.43
Answer:
Molly's Z score for LSAT
z-score=-2
Molly's Z score for MCAT
z-score=2
Step-by-step explanation:
z-score for LSAT
Molly's score=120
mean=150
Standard deviation=15
z-score= (Molly LSAT score-mean)/standard deviation
z=120-150/15=-30/15=-2
z-score for MCAT
Molly's score=52
mean=40
Standard deviation=6
z-score= (Molly MCAT score-mean)/standard deviation
z=52-40/6=12/6=2
You can work out the percentage change and that would help you work out the rate of appreciation :)
The formula is ((new value - old value)/old value) * 100.
So you do 
Therefore the rate of appreciation is 8% p/a.
Answer:
The original price of her purchase was $65.
Step-by-step explanation:
From the information given, you know that $13 represents 20% of the original price and you can use a rule of three to find the value that represents 100%, which would be the original pice of her purchase:
$13 → 20%
x ← 100%
x=(13*100)/20
x=1300/20
x=65
According to this, the answer is that the original price of her purchase was $65.
PEMDAS
(9)(5) + 8
45 + 8
53