All categories

3 years ago

Compare and contrast multiplication prop of equality and inequality

Mathematics

2 answers:

Alex3 years ago

7 0

Answer:

Difference between multiplication property of equality and inequality

The only difference is: If you multiply or divide both sides of an equation by the same negative number, the equation remains the same, but If you multiply or divide both sides of an inequality by the same negative number, the inequality reverses. !!!!!

Step-by-step explanation:

trasher [3.6K]3 years ago

4 0

For an equality, whether multiplying by a positive or a negative number, the equality is maintained.

For an inequality, multiplying (or dividing) by a negative number requires that the inequality sign be reversed. When multiplying (or dividing) by a positive number, the inequality sign remains as it was.

You might be interested in

A kitchen floor has 15 1/2 tiles in an area of 2 2/5 square feet. How many tiles are in one square foot?

Marat540 [252]

6 2/5 is the answer, because 15 1/2 divided by 2 2/5 is 6 2/5

6 0

3 years ago

Line h is represented by the following equation 2x+2y=8

finlep [7]

Answer:

Step-by-step explanation:

To have infinitely many solutions, the lines must be identical consisting of exactly the same points to make it. This means when in simplest form their equations are the same as well.

Simplify 2x+2y=8 by dividing by 2 throughout the entire equation. It becomes x+y = 4. This equation matches B.

7 0

3 years ago

The mean of a population is 74 and the standard deviation is 15. The shape of the population is unknown. Determine the probabili

Lena [83]

Answer:

a) 0.0548 = 5.48% probability of a random sample of size 36 yielding a sample mean of 78 or more.

b) 0.9858 = 98.58% probability of a random sample of size 150 yielding a sample mean of between 71 and 77.

c) 0.5793 = 57.93% probability of a random sample of size 219 yielding a sample mean of less than 74.2

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 estabilishes 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.

The mean of a population is 74 and the standard deviation is 15.

This means that $\mu = 74, \sigma = 15$

Question a:

Sample of 36 means that $n = 36, s = \frac{15}{\sqrt{36}} = 2.5$

This probability is 1 subtracted by the pvalue of Z when X = 78. So

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

By the Central Limit Theorem

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

$Z = \frac{78 - 74}{2.5}$

$Z = 1.6$

$Z = 1.6$ has a pvalue of 0.9452

1 - 0.9452 = 0.0548

0.0548 = 5.48% probability of a random sample of size 36 yielding a sample mean of 78 or more.

Question b:

Sample of 150 means that $n = 150, s = \frac{15}{\sqrt{150}} = 1.2247$

This probability is the pvalue of Z when X = 77 subtracted by the pvalue of Z when X = 71. So

X = 77

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

$Z = \frac{77 - 74}{1.2274}$

$Z = 2.45$

$Z = 2.45$ has a pvalue of 0.9929

X = 71

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

$Z = \frac{71 - 74}{1.2274}$

$Z = -2.45$

$Z = -2.45$ has a pvalue of 0.0071

0.9929 - 0.0071 = 0.9858

0.9858 = 98.58% probability of a random sample of size 150 yielding a sample mean of between 71 and 77.

c. A random sample of size 219 yielding a sample mean of less than 74.2

Sample size of 219 means that $n = 219, s = \frac{15}{\sqrt{219}} = 1.0136$

This probability is the pvalue of Z when X = 74.2. So

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

$Z = \frac{74.2 - 74}{1.0136}$

$Z = 0.2$

$Z = 0.2$ has a pvalue of 0.5793

0.5793 = 57.93% probability of a random sample of size 219 yielding a sample mean of less than 74.2

5 0

3 years ago

Download guathmath and put it my code please it's an app with tutors it's faster! WFHUZJ

timofeeve [1]

Answer: Advertisement?

Do I need an explanation? : Y e s I d o

7 0

3 years ago

How much cashews at $1.58 per pound must be mixed with walnuts that cost 78 cents per pound to make a mixture of 40 pounds of nu

Likurg_2 [28]

Number of pounds of cashews is 36 pounds and number of pounds of walnuts is 4 pounds.

Step-by-step explanation:

Step 1: Given details are cost of cashews = $1.58, cost of walnuts = 78 cents = $0.78, total weight of nuts = 40 pounds, cost of nuts per pound = $1.50

Step 2: Let number of pounds of cashews to be mixed be C, then number of pounds of walnuts will 40 - C. Form equation with these variables.

⇒ 1.58 C + (40-C) 0.78 = 40 × 1.50

⇒ 1.58 C + 31.2 - 0.78 C = 60

⇒ 1.58 C - 0.78 C = 60 - 31.2

⇒ 0.8 C = 28.8

⇒ C = 36 pounds

Step 3: Calculate number of pounds of walnuts

⇒ Number of pounds of walnuts = 40 - C = 4 pounds

5 0

3 years ago

Read 2 more answers