Answer:
F(x-h) = x² + 2xh +h² +2
Step-by-step explanation:
F(x) = x² + 2, x∈R
F(x + h) = (x + h )² + 2 = x² + 2xh + h² + 2
29.75/8.5=x/4.5
using the "butterfly method"
8.5x=133.875
/8.5 /8.5
x=15.75
You have to make a proportion
Answer:
The 95% margin of error for this estimate is 0.0274 = 2.74 percentage points.
Step-by-step explanation:
In a sample with a number n of people surveyed with a probability of a success of 
, and a confidence level of 
, we have the following confidence interval of proportions.
In which
z is the zscore that has a pvalue of 
.
The margin of error is:
95% confidence level
So 
, z is the value of Z that has a pvalue of 
, so 
.
72% of Americans said that they had at least one credit card
This means that 
Give the 95% margin of error for this estimate.
The 95% margin of error for this estimate is 0.0274 = 2.74 percentage points.
Answer:
80 hours
Step-by-step explanation:
let d represent doug, let l represent laura
first, set up a system of equations representing the problem:
since doug spent 10 less than twice the hours laura did, and we know that the total amount of hours they spent together is 230:
l=2d+10
d+l=230
then solve:
*first i rearranged the equations so i can solve this system of equations using elimination method*
l-2d=10
l+d=230
*subtract*
3d=240
d=80
so, doug spent 80 hours in the lab
