Search
1.9.given A "\\begin{bmatrix}\n 1 & 1& -1 \\\\\n 2 & 2 & 3 \\\\\n 4 & 0 &0 \\\\\n \n\\end{bmatrix}" B="\\begin{bmatrix}\n 1 & 1 & -1 \\\\\n 2 & 2 & 3 \\\\\n 4 & 0 & 0 \\\\\n\n\\end{bmatrix}"
1.9.1. find -A -1 +3BT
1.9.2. Find B-1+(AT+A-1)
The heights of male are normally distributed with mean of 170 cm and standard deviation of 7.5cm. Find the probability that a randomly selected male has a height > 180 cm.
Customers arrive at a shopping mart randomly at a rate of 7 per hour.
a) Find the probability that during any 90 minutes’ period, the number of customers arriving at the shopping mart is exactly 8.
b) If a customer arrives at 11.30 am, find the probability that the next patient arrives before 11.45 am.
1.use Cramer's rule to solve the equation below (10 marks)
y-z =2
3x+2y+z=4
5x+4y=1
The average on a history exam was 85 out of 100 points, with a standard deviation of 15. Was the distribution of the scores on this exam symmetric? If not, what shape would you expect this distribution to have? Explain your reasoning.
At a restaurant 80% of the users pay using credit cards. Find the probability that in a randomly selected sample of 5 users, exactly 2 users pay using credit cards.
1.4 If Universal Set U = {90, 91 , 92 , 93 , 94, 95 , 96 , 97 , 98, 99 , 100} (10) A = {90, 92, 94, 96, 98, 100}, B= {91, 93, 95, 97, 99}, C = {90, 94, 98}
1.4.1 What is (A ∩ C)c
1.4.2 What is (B ∪ C)c
3. What is the 99.5th percentile in a t-distribution with 9 degrees of freedom?
a. 2.764 b. 3.250 c. 3.169 d. 2.821
4. To estimate the mean price of e-books of senior high schools, with a standard deviation of P80, how many e-books are needed to be selected as samples if we wanted to be 95% confident that the sample mean of e-books is within P20 of the true population?
a. 59. b. 60 c. 61 d. 62
5. Which of the following is the appropriate sample size given a standard deviation of 6.4, confidence interval of u 98% and a margin of error or maximum allowable deviation of 2.35?
a. 39 b. 40 c. 41 d. 42
1. t - distribution is a probability distribution used to estimate parameters EXCEPT
when :
a.. the population standard deviation is known
b. the sample size is small.
d. the sample size is small and population variance is unknown
2. t distribution is also known as:
c. the population variance is unknown
a. Teacher's t distribution b. z-distribution
c. Student's t - distribution d. Teacher's z - distribution
Show that {𝑥} ⊆ ℝ is connected
