<u>Answer</u>:
c = 9
<u>Explanation</u>:
given: f(x)=3x-7
<em>if f(c) =20</em>
To solve this replace x with c and then y is 20.
<u>Solve</u>:
3c - 7 = 20
3c = 27
c = 27 ÷ 3
c = 9
Answer:
There are 3 adults in the family.
Step-by-step explanation:
The equations 8x + 4y = 32 and 16x + 12y = 72 represent the cost of lunch and dinner for a family in which x is the number of adults and y is the number of children.
We have to find the number of adults or the value of x by solving these equations.
equations are 8x + 4y = 32 -------(1)
16x + 12y = 72 --------(2)
Now we will multiply equation 1 by 3 and subtract it by equation 2.
(16x + 12y) -3(8x + 4y) = 72 - 96
16x + 12y - 24x - 12y = -24
(16x - 24x) + (12y - 12y) = -24
-8x = - 24
8x = 24
x = 3
Therefore, there are 3 adults in the family.
Answer:
The degrees of freedom for this sample are 27.
The sample size to get a margin of error equal or less than 0.3656 is n=4450.
Step-by-step explanation:
The degrees of freedom for calculating the value of t are:
With 27 degrees of freedom and 95% confidence level, from a table we can get that the t-value is t=2.052.
The sample size to get a margin of error equal or less than 0.3656 can be calculated as:
T + 49 This is the answer because by saying “more than” you are adding and the symbol for adding is “+”.
