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4 years ago

Please explain the how you got the answers thanks asap

Mathematics

1 answer:

stich3 [128]4 years ago

5 0

Answer:

a) 90 stamps

b) 108 stamps

c) 333 stamps

Step-by-step explanation:

Whenever you have ratios, just treat them like you would a fraction! For example, a ratio of 1:2 can also look like 1/2!

In this context, you have a ratio of 1:1.5 that represents the ratio of Canadian stamps to stamps from the rest of the world. You can set up two fractions and set them equal to each other in order to solve for the unknown number of Canadian stamps. 1/1.5 is representative of Canada/rest of world. So is x/135, because you are solving for the actual number of Canadian stamps and you already know how many stamps you have from the rest of the world. Set 1/1.5 equal to x/135, and solve for x by cross multiplying. You'll end up with 90.

Solve using the same method for the US! This will look like 1.2/1.5 = x/135. Solve for x, and get 108!

Now, simply add all your stamps together: 90 + 108 + 135. This gets you a total of 333 stamps!

You might be interested in

Which are acute, obtuse, or right?

qaws [65]

5,7 and 8 are right angles, and 6 is an acute angle this is because of u look at 9 and 10 you can see a little box looking thing under the h and if u do that to all of them 5, 7 and 8 can fit the little box but 6 you can’t because it is an acute angle. Hope this helped!

8 0

4 years ago

We are interested in determining whether or not the variances of the sales at two small grocery stores are equal. A sample of 21

katen-ka-za [31]

Answer:

$F=\frac{s^2_A}{s^2_B}=\frac{28.284^2}{20^2}=1.99996$

Step-by-step explanation:

Data given and notation

$n_A = 21$ represent the sampe size for A

$n_B =16$ represent the sample size for B

$s_A = 28.284$ represent the sample deviation for A

$s_B = 20$ represent the sample deviation for B

$\alpha$ represent the significance level provided

F test is a statistical test that uses a F Statistic to compare two population variances, with the sample deviations s1 and s2. The F statistic is always positive number since the variance it's always higher than 0. The statistic is given by:

$F=\frac{s^2_1}{s^2_2}$

Solution to the problem

System of hypothesis

We want to test if we have the same variation, so the system of hypothesis are:

H0: $\sigma^2_A = \sigma^2_B$

H1: $\sigma^2_A \neq \sigma^2_B$

Calculate the statistic

Now we can calculate the statistic like this:

$F=\frac{s^2_A}{s^2_B}=\frac{28.284^2}{20^2}=1.99996$

8 0

4 years ago

Consider the following sample set of scores. Assume these scores are from a discrete distribution. 21 29 32 38 38 45 50 64 72 10

ASHA 777 [7]

Answer:

Original data: 21 29 32 38 38 45 50 64 72 100

$\bar X = \frac{21+29+32+38+38+45+50+64+72+100}{10}=48.9$

Mode =38.

$Median = \frac{38+45}{2}=41.5$

Change 1: 2 29 32 38 38 45 50 64 72 100

$\bar X = \frac{2+29+32+38+38+45+50+64+72+100}{10}=47$

Mode =38.

$Median = \frac{38+45}{2}=41.5$

Change 2: 29 32 38 38 45 50 64 72 100

$\bar X = \frac{29+32+38+38+45+50+64+72+100}{9}=52$

Mode =38.

$Median = 45$

Step-by-step explanation:

Original data: 21 29 32 38 38 45 50 64 72 100

The mean is calculated with the following formula:

$\bar X = \frac{\sum_{i=1}^{10} X_i}{10}$

And if we replace we got:

$\bar X = \frac{21+29+32+38+38+45+50+64+72+100}{10}=48.9$

The mode is the most repeated value in the sample and on this case is Mode =38.

Since we have an even number of points the median is calculated as the average between the observations 5 and 6 from the dataset ordered.

$Median = \frac{38+45}{2}=41.5$

Change 1: 2 29 32 38 38 45 50 64 72 100

The mean is calculated with the following formula:

$\bar X = \frac{\sum_{i=1}^{10} X_i}{10}$

And if we replace we got:

$\bar X = \frac{2+29+32+38+38+45+50+64+72+100}{10}=47$

The mode is the most repeated value in the sample and on this case is Mode =38.

Since we have an even number of points the median is calculated as the average between the observations 5 and 6 from the dataset ordered.

$Median = \frac{38+45}{2}=41.5$

Change 2: 29 32 38 38 45 50 64 72 100

Now the sample size is 9 instead of 10

The mean is calculated with the following formula:

$\bar X = \frac{\sum_{i=1}^{9} X_i}{9}$

And if we replace we got:

$\bar X = \frac{29+32+38+38+45+50+64+72+100}{9}=52$

The mode is the most repeated value in the sample and on this case is Mode =38.

Since we have odd number of points the median is calculated from the 5 position of the dataset ordered.

$Median = 45$

7 0

4 years ago

I will give you BRAINLIEST for the correct answer

Verizon [17]

B. 15:12, 15 to 12, 15/12

3 0

3 years ago

Amelia is using substitution to determine if 8 is a solution to the equation. Complete the statements. 6a = 42 for a = 8 First,

Tju [1.3M]

Amelia must substitute 8 for the variable using parentheses. To simplify, Amelia must multiply 8 by 6. 8 is not a solution of the equation.

<h3>What is algebraic expression?</h3>

Algebraic expression are the expression which consist the variables, coefficients of variables and constants.

The algebraic expression are used represent the general problem in the mathematical way to solve them.

Amelia is using substitution to determine if 8 is a solution to the equation. The equation which is Amelia is solving for a = 8 is,

$6a = 42$

First, Amelia must substitute 8 for the variable using parentheses as,

$6(8) = 42$

To simplify, Amelia must. multiply 8 by 6.

$48 \neq 42$

The left hand side of the eqqation is not equal to the right hand side. Thus, 8 is not a solution of the equation.

Thus, Amelia must substitute 8 for the variable using parentheses. To simplify, Amelia must multiply 8 by 6. 8 is not a solution of the equation.

Learn more about the algebraic expression here;

brainly.com/question/2164351

4 0

2 years ago