It is claimed that the mean annual salary of call center customer service representative is php 188 584.00. A researcher randomly selected 45 call center customer service representative. He computed the mean of their annual salaries and obtained a mean of php 188 600.00. Does this show that the mean salary of call center customer service representatives is greater than php 188 584.00? Use 0.05 level of significance and assume that the population standard deviation is php 39.50.
How much Sodium Phosphate do we need to add to the water over 1 day in grams, to remove the dissolved iron.
The recomended concentration of sodium phosphate is 7.0mg/L
The amount of iron dissolved in the water is 13.84mg/L
4 300 000L of water go through the city each day.
A company which produces batteries claims that the life expectancy of their batteries is 90 hours in order to test the claim a consumer interest group tested a random sample of 40 batteries. The test resulted to a mean life expectancy of 87 hours. Using a 0.05 level of significance, can it be concluded that the life expectancy of their batteries is less than 90 hours? Assume that the population standard deviation is known to be 10 hours.
The head of the math department announced that the mean score of grade 11 students in the first periodic examination isn mathematics was 89 and the standard deviation was 12. One student believed that the mean score was less than this, randomly selected 34 students and computed their mean score. She obtained a mean score of 85. At 0.01 level of significance, test the students belief.
A medical practitioner wants to estimate the mean systolic blood pressure in pre-school children with inbom heart disease. He plans on using a 99% confidence interval and a margin of error of 5 units. The standard deviation of systolic blood pressures in pre-school children with inborn heart disease is 20. How many children should be enrolled in the study?
An Environmentalist is making a survey on the number of households that applies the principles of Waste Management in a certain community. Given the standard deviation of 26, how large a sample must be selected if we want to be 95% confident of finding whether the true mean differs from the sample mean by 1.5 hour?
What is the probability of both coins landing on heads?
96.0 g. of a gas occupies 48.0 L at 700.0 mm Hg and 20.0°C. What is its molar mass?
For the following reaction:
A(aq) + 2 B(aq) ⇌ 2 C(aq) + 2 D(aq)
Calculate the magnitude of Kc (don't report the units) assuming the following composition at equilibrium:
[A] = 0.876 mol L-1
[B] = 0.708 mol L-1
[C] = 0.929 mol L-1
[D] = 0.328 mol L-1
Given the function defined in the table below, find the average rate of change, in simplest form, of the function over the interval 1\le x \le 5
1≤x≤5.