Find the value of m. A. 7 B. 2 C. 42 D. 14

Mathematics

1 answer:

lina2011 [118]3 years ago

7 0

Answer:

A. 7

Step-by-step explanation:

3m + 21 = 6m

Move variables to one side to get:

3m + 21 = 6m

-3m -3m

21 = 3m

Then isolate variable by dividing by 3

21/3 = 3m/3

m = 7

Choice A is the correct answer

You might be interested in

Please explain absolute values?

myrzilka [38]

Answer:

the magnitude of a real number without regard to its sign.

Step-by-step explanation:

For example, |-3| would just be a 3 in general, no negative sign in the front.

hope this answers your confusion.

7 0

3 years ago

Read 2 more answers

Find the population mean or sample mean as indicated. Sample: 19, 15, 6, 11, 24 Compute the sample mean for this data set. Selec

yKpoI14uk [10]

Answer:

$\overline{x}=15$

Step-by-step explanation:

the mean is given by:

$\overline{x} = \dfrac{\sum\limits_{i=1}^n x_i}{n} \quad\text{or}\quad \dfrac{\text{sum of all items}}{\text{number of items}}$

In our case this is:

$\overline{x} = \dfrac{19+15+6+11+24}{5} \Rightarrow \dfrac{75}{5}\\\\\overline{x} = 15\\\\$

side note: the main difference between sample mean and population mean is in the 'context'. However, the method to calculate them is the same.

By context I mean: if this the items are taken from some larger category for example: the ages of a few 'students' from a 'class'. Here 'students' are the sample from a larger set that is 'class'. The mean of the 'few students' will be called sample mean. In contrast, if we take the mean of the ages of the whole class then this is called population mean. (population mean == mean of the whole set)

In our case we aren't told exactly where these numbers come from, is this the whole set or a sample from it, the lack of context allows us to assume that the mean can either be population mean or sample mean. So we can safely use any symbol $\mu$ or $\overline{x}$ .