Answer:20%
Step-by-step explanation
When you multiply 64x100, you'd get 6400. Then you divide that by 80, you get 80. And when you have 80/100, you have 20 left out of the 100. So it is 20%.
0. 6 0 0
5 3. 0 0 0
− 0
3 0
− 3 0
0 0
− 0
0 0
− 0
0
Answer:
15%
Step-by-step explanation:
set up 15/20= x/100
cross multiply to solve for x
1500=20x
x= 75
15 dollars is 75% of the original price, so there was a 15% change
Answer:
5x-6
Step-by-step explanation:
f(x) = 2x + 3
g(x) = 3x - 9
f(x) + g(x) = 2x + 3 + 3x-9
= 5x-6
Answer:
They can either decrease the confidence level or increase the sample size, that is, survey more students.
Step-by-step explanation:
The width of a confidence interval is given by:

In which z is the critical value correponding to the confidence level(higher confidence level, higher z is),
is the standard deviation of the population and n is the size of the sample.
The students realize that this interval contains a large margin of error. What can they do to make a narrower interval?
Looking at the formula for M, they can either decrease the confidence level or increase the sample size, that is, survey more students.