Keywords:
<em>Function, variable, total cost, percentage, jeans
</em>
For this case we have a function of the form
, where 
represents the total cost of buying a pair of jeans, considering that they are 20% below the regular price given by the variable x.
So, if the pair of jeans costs x, we look for 20% of x.
x -----------> 100%
? -----------> 20%
Where "?" represents 20% of x. So, we have:
Thus, 0.2x represents the reduction of the total cost of the pair of jeans
Then, the function that gives the total cost of the pair of jeans, with a reduction of 20% is:
Answer:
Option C
So we have the formula:
where
is the distance in kilometers
is the petrol in liters
is the petrol consumption in kilometers per liter
We now for our problem that <span>David drove a distance of 187 km, so </span>
. We also know that he used 28 liters of petrol, so
. Lets replace those values in our formula to find the petrol consumption:
Now, remember that are some rules to determine the number of significant figures in a number:
1. Non-zero digits are always significant figures.
2. A zero between tow significant figures is always a significant figure.
Applying those tow rules we realize that
has 6 significant figures, whereas
has three significant figures and
only two. In mathematical operations with significant figures, the answer should be given with the same significant figures as the number with least significant figures involved in the operations. In our case, that number is
, and
has two significant figures, so our answer should have 2 significant figures. To give our answer with 2 significant figures, we are going to round it:
We can conclude that the patrol consumption of David's vehicle is
6.7 kilometers per liter.
$794-$213.75= $580.25
Check payment would be taken out of her account.
By definition, the pitch of a roof is its vertical rise divided (In this case is 7 feet) by its horizontal measurement, which is called "Run" (42 feet). Therefore, you can calculate the pitch of this roof (P) by applying the following steps:
P=Tan^-1(Rise/Run) Rise=7 feet
Run=42 feet
When you substitute these values into the formula P=Tan^-1(Rise/Run), you obtain:
P=Tan^-1(Rise/Run)
P=Tan^-1(7/42) P=9.46º
<span>What is the pitch of the roof?
</span>
The answer is: The pitch of the roof is 9.46º.
You have 7 and so to get a mixed number is like this 7/1 then back to 7 because there is no way to get a mixed number with just the number 7.
