D should be the correct answer
Answer:
old town has 150 steps
Step-by-step explanation:
Let the number of steps in the old tower be m
Mathematically, time = distance/speed
In this case, the distance is the number of steps while the speed is the rate of climbing or descending
For climbing, time spent = m/3
For descending time spent = m/2
Since it took her 25 longer when descending;
This means that;
m/2 - m/3 = 25
(3m-2m)/6 = 25
m/6 = 25
m = 6 * 25
m = 150 steps
Answer:
brainliest please
Step-by-step explanation:
x/3-2<4
x/3<6
x<18
Answer:
The minimum sample size needed is 125.
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:

For this problem, we have that:

99% confidence level
So
, z is the value of Z that has a pvalue of
, so
.
What minimum sample size would be necessary in order ensure a margin of error of 10 percentage points (or less) if they use the prior estimate that 25 percent of the pick-axes are in need of repair?
This minimum sample size is n.
n is found when 
So






Rounding up
The minimum sample size needed is 125.
It will take about 16.66 months for the investment to double.
Hope this helps.