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2 years ago

Ms. Hamby gave a quiz. Two students’ work and the answer key are shown. Ms. Hamby accepts equivalent answers in any form.

Mathematics

1 answer:

Luden [163]2 years ago

5 0

Answer:

Student A and Student B both answered 2 questions correctly.

See explanation below

Step-by-step explanation:

Note: that answers in the form:

$\frac{a}{-b}=\frac{-a}{b}=-\frac{a}{b}$

ARE ALL EQUIVALENT.

First of all, 4/5 is equivalent to 0.8 if we do long division.

and 19/20 is 0.95 if we do long division.

Now, <u>Student A:</u>

Both of the fractions are correct and the negative sign is equivalent and makes the answer correct, so both are correct.

For <u>Student B:</u>

Similarly, both answers are correct for this student as well, looking at the equivalence we showed first.

Also, "-" (negative) in front of the parenthesis and inside parenthesis here doesn't matter.

Hence,

Student A and Student B both answered 2 questions correctly.

You might be interested in

A botanist collected one leaf at random from each of 10 randomly selected mature maple trees of the same species. The mean and t

Zarrin [17]

Answer:

One sample t-test for population mean would be the most appropriate method.

Step-by-step explanation:

Following is the data which botanist collected and can use:

Sample mean
Sample Standard Deviation
Sample size (Which is 10)
Distribution is normal

We have to find the best approach to construct the confidence interval for one-sample population mean. Two tests are used for constructing the confidence interval for one-sample population mean. These are:

One-sample z test for population mean
One-sample t test for population mean

One sample z test is used when the distribution is normal and the population standard deviation is known to us. One sample t test is used when the distribution is normal, population standard deviation is unknown and sample standard deviation is known.

Considering the data botanist collected, One-sample t test would be the most appropriate method as we have all the required data for this test. Using any other test will result in flawed intervals and hence flawed conclusions.

Therefore, One-sample t-test for population mean would be the most appropriate method.

8 0

2 years ago

What is the difference between factoring and solving ?

trapecia [35]

Answer:

Factoring is a step taken towards solving a quadratic equation. ... You cannot factor them, the only way to find the roots then, is by using the quadratic formula. Suppose you factor the quadratic polynomial as and . Then set them equal to zero and solve for , you will have

Step-by-step explanation.

Example 1 – Solve: x2 + 16 = 10x

Step 1: Write the equation in the correct form. In this case, we need to set the equation equal to zero with the terms written in descending order.

Step 2: Use a factoring strategies to factor the problem.

Step 3: Use the Zero Product Property and set each factor containing a variable equal to zero.

Step 4: Solve each factor that was set equal to zero by getting the x on one side and the answer on the other side.

6 0

2 years ago

The results of a mathematics placement exam at two different campuses of Mercy College follow: Campus Sample Size Sample Mean Po

Leona [35]

Answer:

$z=\frac{(33-31)-0}{\sqrt{\frac{8^2}{330}+\frac{7^2}{310}}}}=3.37$

$p_v =P(Z>3.37)=1-P(Z$

Comparing the p value with a significance level for example $\alpha=0.05$ we see that $p_v$ so we can conclude that we have enough evidence to reject the null hypothesis, and we can say that the mean for the Campus 1 is significantly higher than the mean for the group 2.

Step-by-step explanation:

Data given

Campus Sample size Mean Population deviation

1 330 33 8

2 310 31 7

$\bar X_{1}=33$ represent the mean for sample 1

$\bar X_{2}=31$ represent the mean for sample 2

$\sigma_{1}=8$ represent the population standard deviation for 1

$\sigma_{2}=7$ represent the population standard deviation for 2

$n_{1}=330$ sample size for the group 1

$n_{2}=310$ sample size for the group 2

$\alpha$ Significance level provided

z would represent the statistic (variable of interest)

Concepts and formulas to use

We need to conduct a hypothesis in order to check if the mean for Campus 1 is higher than the mean for Campus 2, the system of hypothesis would be:

Null hypothesis: $\mu_{1}-\mu_{2}\leq 0$

Alternative hypothesis: $\mu_{1} - \mu_{2}> 0$

We have the population standard deviation's, and the sample sizes are large enough we can apply a z test to compare means, and the statistic is given by:

$z=\frac{(\bar X_{1}-\bar X_{2})-\Delta}{\sqrt{\frac{\sigma^2_{1}}{n_{1}}+\frac{\sigma^2_{2}}{n_{2}}}}$ (1)

z-test: Is used to compare group means. Is one of the most common tests and is used to determine whether the means of two groups are equal to each other.

With the info given we can replace in formula (1) like this:

$z=\frac{(33-31)-0}{\sqrt{\frac{8^2}{330}+\frac{7^2}{310}}}}=3.37$

P value

Since is a one right tailed test the p value would be:

$p_v =P(Z>3.37)=1-P(Z$

5 0

2 years ago

What is the length of Line segment A B? Round to the nearest tenth. Triangle A B C is shown. Angle A C B is a right angle and an

amm1812

C=90°, A=75°, b=AC=19, x=AB

Without a figure, we see AC is adjacent to angle A, so

cos A = AC/AB = b/x

x = b/cos A = 10 / cos 75° ≈ 38.637

Answer: 38.6

3 0

2 years ago

Read 2 more answers

The box which measures 70cm X 36cm X 12cm is to be covered by a canvas. How many meters of canvas of width 80cm would be require

grigory [225]

Answer:

142.2 meters.

Step-by-step explanation:

We have been given that a box measures 70 cm X 36 cm X 12 cm is to be covered by a canvas.

Let us find total surface area of box using surface area formula of cuboid.

$\text{Total surface area of cuboid}=2(lb+bh+hl)$ , where,

$l$ = Length of cuboid,

$b$ = Breadth of cuboid,

$w$ = Width of cuboid.

$\text{Total surface area of box}=2(70\cdot36+36\cdot 12+12\cdot 70)$

$\text{Total surface area of box}=2(2520+432+840)$

$\text{Total surface area of box}=2(3792)$

$\text{Total surface area of box}=7584$

Therefore, the total surface area of box will be 7584 square cm.

To find the length of canvas that will cover 150 boxes, we will divide total surface area of 150 such boxes by width of canvass as total surface area of canvas will also be the same.

$\text{Width of canvas* Length of canvass}=\text{Total surface area of 150 boxes}$