Search & Filtering
A company claimed that their N95 face mask has a mean filtration efficiency rate of
95%. A group of student researcher wanted to verify this claim. They bought and tested
40 of their N95 face masks. They found out that the average filtration efficiency rate of
these face mask was 90% with a standard deviation of 4%. Test the claim at 5% level
of significance and assume that the population is approximately normally distributed.
A survey unofficially claimed that in every five young executives, only one practices good reading habits.
a. What is the probability that out of 10 young executives, two executives practice good reading habits?
b. What is the probability that at least five out of 20 young executives practice good reading habits?
the following data were obtained by sampling a population
5
3
7
5
6
8
6
5
9
Compute for the mean.
A population has mean 75 and standard deviation 12.
a.)Random samples of size 121 are taken. Find the mean and standard deviation of sampling distribution of the means?
b.)How would the answers to part (a) change if the size of the samples were 400 instead of 121?
How many ways are there to select 12 countries in the United Nations to serve on a council if 2 is selected from a block of 55, 2 are selected from a block of 67 and 8 are selected from the remaining 67 countries
find the class boundaries, midpoint, and width for the class 12.4-15.2
In modern mathematics teaching we want relational understanding, in addition to instrumental understanding. Describe how a teacher would teach for both instrumental and relational understanding of long division 357÷19.
Teaching long division of 357÷19 for instrumental understanding
Teaching long division of 357÷19 for relational understanding
A company makes products A and B. Each unit of product A requires 1 unit of resource 1 and 5 units
of resource 2. Each unit of product B requires 5 units of resource 1 and 4 units of resource 2. If there
are 40 units of resource 1 and 140 units of resource 2 available, how many units of each product should
be produced if all the resources are to be used?
Solve this system of equations and provide a graphical representation of the solution. (12)
x2 + y2 = 5
x + y = 1
3.1 Write a number sentence that will represent the structure of the following problem situations. 3.1.1 Nare had some marbles. After receiving 24 from his sister, he now has 52 marbles altogether. How many marbles did Nare have at the beginning? (2) 3.1.2 Gabriel and Miranda have R257 between them. Gabriel has R165. How much does Miranda have? (3.1.3 Shaheed bought 3 chickens for R94 each from a local supermarket. She also bought a bag of potatoes. Shaheed paid R282 in total. How much did the potatoes cost? (2) 3.1.4 Phumzile is 6 years younger than her brother, Piet. How old is Piet when Phumzile is 25 years old? (2) 3.1.5 The young ostrich, Lenka, has to take 3 steps to keep up with every step taken by her mother. How many steps must Lenka take when her mother takes 6 steps? (2) 3.1.6 Mashudu had R500 in his wallet. After buying some dinner for him and a friend, he now has R220. How much did Mashudu pay for the dinner? (2) 3.2 Name the problem type for each of the problem situations in 3.1.
