Math Answers

Initially, there are 1 million bacteria present in a Petri dish. After 2 minutes, there are already 5 million of them. If the bacterial population follows a law of natural growth, how many bacteria should be present in the Petri dish after 5 minutes?

Consider the constant rate of depreciation value of a certain car. You bought a car amounting to 1.5 million pesos. After 2 years, the value decreased to 1.2 million pesos. If the amount of the car is directly proportional to the constant rate of decay in amount and such decrease in amount continues at the same rate, then how much is the estimated value of the car after 10 years?

Americans ate an average of 25.7 pounds of confectionery products each last year and

spent an average of $61.50 per person doing so. If the standard deviation of consumption is 3.75 pounds and the standard deviation of the amount spent is %5.89, find the following:

a. The probability that the sample mean confectionary consumption for a random sample

of 40 American consumers was greater than 27 pounds.

b. The probability that for a random sample of 50, the sample mean for confectionary

spending exceeded $60.00

The average per capita spending on health care in United States is $5274. If the standard

deviation is $600 and the distribution of health care spending is approximately normal, what is the probability that a randomly selected person spends more than $6000? Find the limits of the middle 50% of individual health care expenditures.

a company produces mosquito repellents that have a period of effectiveness that is approximately normally distributed with a mean of 300 hours and a standard deviation of 30 hours. A sample of 40 repellents was taken and the average period of effectiveness is computed as 290 hours. Test the hypothesis that µ = 300 against the alternative that µ ≠ 300

Four cards are drawn from a desk without replacement. Find these probabilities.

a. All cards are jacks.

b. All cards are black cards.

c. All cards are hearts.

(2<45°)/((3<120°)(4<180°)) leave your answer in rectangular form

A medical trial is conducted to test whether or not a new medicine reduces cholesterol by 25% test at 99% confidence level

How does the t-distribution differ from a normal distribution? A. The t-distribution has a mean of 0. B. The t-distribution has a thicker tail. C. The t-distribution is symmetric in the middle. D. The t-distribution is bell-shaped.

A survey of 300 Senior High School learners shows that they read on average of 20 hours per week with a margin of error of 2.2 hours at 95% level of confidence.

21. What is the sample mean? A. 20 B. 300 C. 2.2 D. 0.05

22. Which of the following is the upper limit of the interval? A. 15 B. 17.8 C. 22.2 D. 1.96

23. What is the lower limit of the confidence interval? A. 17.8 B. 1.96 C. 22.2 D. 4.4

24. What is the length of the confidence interval? A. 17.8 B. 22.2 C. 4.4 D. 2.