Answer:
b = -17
Plug it in to find maybe correct answer if not sure next time.
price after discount- $44-$11=$33
amount of tip- $4.95
bill after discount and tip- $37.95
amount of tax- $2.83
total bill- $40.78
Givens
<em><u>Slower car</u></em>
r = r
t = 12 hours
d = ?
<em><u>Faster car</u></em>
r = r + 20
t = 8 hours
d = ?
It doesn't matter what the exact distance is. You just have to know that the 2 distances are equal ie going to the mountains from his home is the same distance as going from the mountains to his home.
d = r * t
r * 12 hours = (r + 20)* 8 hours. Remove the brackets on the right
r*12 = 8r + 20*8
r*12 = 8*r + 160
r*12 - 8r = 8r - 8r + 160
4r = 160
r = 40 miles / hour
=================
Slower Ride determines the distance.
d = r*t
d = 40 * 12
d = 480
Check
Use the faster rate (r + 20) = 40 + 20 = 60 mph
60 * 8 = 480. Both distances work out to be the same.
Answer:
2.28%
Step-by-step explanation:
Given that:
µ = 40 minutes ; σ = 3.5.
x = > 47 minutes
Obtain the standardized score, Z
Zscore = (x - μ) / σ
P(x > 47) = (47 - 40) / 3.5
P(x > 47) = 7 / 3.5
P(x > 47) = 2
P(z > 2) = 0.02275
Hence, Probability that next pizza delivery takes over 47 minutes is 0.02275 = 2.275% = 2.28%