Answer:
Confidence interval: (0.04649,0.04913)
Step-by-step explanation:
We are given the following in the question:
Sample size, n = 100,000
Number of people who donated, x = 4781
95% Confidence interval:
Putting the values, we get:
is the required 95% confidence interval for the true proportion of their entire mailing list who may donate.
Rearranging the first equation gives:
Substituting this into the other equation gives:
If x=-1:
So
x=-1, y=-5
The amount invested in the account that yields 7% interest is $4000.
The amount invested in the account that yields 12% interest is $1000.
<h3>What are the linear equations that represent the question?</h3>
a + b = 5000 equation 1
0.07a + 0.12b = 400 equation 2
Where:
a = amount invested in the account that yields 7% interest.
b = amount invested in the account that yields 12% interest.
<h3>How much is invested at each rate?</h3>
Multiply equation 1 by 0.07
0.07a + 0.07b = 350 equation 3
Subtract equation 3 from equation 2
0.05b = 50
b = 50 / 0.05
b = 1000
Subtract 1000 from 5000: 5000 - 1000 = 4000
To learn more about linear functions, please check: brainly.com/question/26434260
#SPJ1
Answer:
69 years
Step-by-step explanation:
Sum of Alex's and Ben's current age
= 14 +17
= 31 years
For every year, Alex and Ben will each be one year older. Thus, 2 years would be added to the sum of their ages with each passing year.
Difference in the sum of their ages
= 169 -31
= 138 years
Number of sets of 2 years
= 138 ÷2
= 69
Thus, the sum of their ages will be 169 in 69 years.
Answer:
C
Step-by-step explanation:
The ratio is given as 
= 
in simplest form
However, if we consider each group of 4 X's to 3 O's then the ratio is
→ C
