Answer
Answer
The speedometer is likely to show the speed is either 36.0 mph or 44.0 mph.
To prove
Formula
![Percentage\ error = \frac{error\times 100}{Exact\ value}](https://tex.z-dn.net/?f=Percentage%5C%20error%20%3D%20%5Cfrac%7Berror%5Ctimes%20100%7D%7BExact%5C%20value%7D)
Where error = |Approx value - Exact value |
First case
As given
A speedometer has a percent error of 10%. The actual speed of the car is 40 mph.
Here
Percentage error = 10%
Exact value = 40 mph
error = - (Approx value - Exact value )
= - (Approx value - 40 )
= - Approx value + 40
Put in the formula
![10 = \frac{(-Approx\ value + 40)\times 100}{40}](https://tex.z-dn.net/?f=10%20%3D%20%5Cfrac%7B%28-Approx%5C%20value%20%2B%2040%29%5Ctimes%20100%7D%7B40%7D)
![400 = {(-Approx\ value + 40)\times 100}](https://tex.z-dn.net/?f=400%20%3D%20%7B%28-Approx%5C%20value%20%2B%2040%29%5Ctimes%20100%7D)
Thus
Approx value = 40 - 4
Approx value = 36 mph
Therefore Option (b) is correct .
Second Case
error = (Approx value - Exact value )
= (Approx value - 40 )
= Approx value - 40
Put in the formula
![10 = \frac{(Approx\ value - 40)\times 100}{40}](https://tex.z-dn.net/?f=10%20%3D%20%5Cfrac%7B%28Approx%5C%20value%20-%2040%29%5Ctimes%20100%7D%7B40%7D)
![400 = {(Approx\ value - 40)\times 100}](https://tex.z-dn.net/?f=400%20%3D%20%7B%28Approx%5C%20value%20-%2040%29%5Ctimes%20100%7D)
Thus
Approx value = 40 + 4
Approx value = 44 mph
Therefore Option (c) is correct .
Answer:
BECAUSE SHE WAS MEAN
Step-by-step explanation:
Answer:
12 hours
Step-by-step explanation:
Let the number of hours be represented as h.
Sarah's surfboards charges a fee of $60 to rent a surfboard and then $10.50 per hour.
Mathematically ,
60 + 10.50h
Sally's surfboards does not charge a fee, but they cost $15.50 per hour
Mathematically,
15.50h
Equating both equations together
60 + 10.50h = 15.50 h
Collect like terms
60 = 15.50h - 10.50h
60 = 5h
h = 60/5
h = 12 hours
Therefore, the number of hours that the cost will be the same to rent a surfboard for each shop is 12 hours.
Answer:
f(- 3) = - 27
Step-by-step explanation:
substitute x = - 3 into the expression
f(- 3) = 9 + (12 × - 3 ) = 9 + (- 36) = 9 - 36 = - 27