How can I work this problem in adding integers with counters 5 + (-7)

Which expression is equivalent to 7z + 7z?

Ierofanga [76]

Answer:

$14z$

Step-by-step explanation:

Since these are like-terms, they can be added together.

7z + 7z = 14z

6 0

3 years ago

Select other ways to express 10². Mark all that apply.

Elanso [62]

F and D is the answer
hope this helps
have a good day

7 0

3 years ago

Read 2 more answers

The value in cents of 4 quarters and x dimes is

Zina [86]

To add numbers, their units should be the same. We need first to convert the quarters and dimes into cents.
4 quarters is equal to 100 cents, while a dime is equal to 10 cents.
In formula, the answer would be 100+10x. ( x refers to the number of dimes)

4 0

3 years ago

Life Expectancies In a study of the life expectancy of people in a certain geographic region, the mean age at death was years an

Sphinxa [80]

Answer:

The probability that the mean life expectancy of the sample is less than X years is the p-value of $Z = \frac{X - \mu}{\frac{\sigma}{\sqrt{n}}}$ , in which $\mu$ is the mean life expectancy, $\sigma$ is the standard deviation and n is the size of the sample.

Step-by-step explanation:

To solve this question, we need to understand the normal probability distribution and the central limit theorem.

Normal Probability Distribution

Problems of normal distributions can be solved using the z-score formula.

In a set with mean $\mu$ and standard deviation $\sigma$ , the z-score of a measure X is given by:

$Z = \frac{X - \mu}{\sigma}$

The Z-score measures how many standard deviations the measure is from the mean. After finding the Z-score, we look at the z-score table and find the p-value associated with this z-score. This p-value is the probability that the value of the measure is smaller than X, that is, the percentile of X. Subtracting 1 by the p-value, we get the probability that the value of the measure is greater than X.

Central Limit Theorem

The Central Limit Theorem establishes that, for a normally distributed random variable X, with mean $\mu$ and standard deviation $\sigma$ , the sampling distribution of the sample means with size n can be approximated to a normal distribution with mean $\mu$ and standard deviation $s = \frac{\sigma}{\sqrt{n}}$ .

For a skewed variable, the Central Limit Theorem can also be applied, as long as n is at least 30.

We have:

Mean $\mu$ , standard deviation $\sigma$ .

Sample of size n:

This means that the z-score is now, by the Central Limit Theorem:

$Z = \frac{X - \mu}{\frac{\sigma}{\sqrt{n}}}$

Find the probability that the mean life expectancy will be less than years.

The probability that the mean life expectancy of the sample is less than X years is the p-value of $Z = \frac{X - \mu}{\frac{\sigma}{\sqrt{n}}}$ , in which $\mu$ is the mean life expectancy, $\sigma$ is the standard deviation and n is the size of the sample.

8 0

2 years ago

Which method do you prefer to use to find sums- count by tens and ones, use compatible numbers, or use friendly numbers and adju

Usimov [2.4K]

I prefer to use compatible numbers because by using this method it is easier to make a sum mentally. This is true because compatible numbers are close in value to the actual numbers. For a better understanding, let's take an example:

Suppose you have two numbers, namely 640 and 40. These two numbers are compatible for division because:

64 ÷ 4 = 16

So, we have used mental arithmetic to solve a more complex problem.

7 0

3 years ago

Read 2 more answers