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2 years ago

. A movie company sells DVDs on line. Each

Mathematics

1 answer:

ELEN [110]2 years ago

4 0

Multiply by cost of a dvd by the number of dvds bought ( x) and add the shipping charge.

A) 33.44 = 9.95x + 3.59

Subtract 3.59 from both sides.

29.85 = 9.95x

Divide both sides by 9.95

X = 29.85/9.95

X = 3

They bought 3 dvds.

B) 33.49-3.59 = 29.85

29.85/9.95 = 3

C) the steps were the same but solving arithmetic you didn’t have to do steps on both sides of an equation.

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Geometry multiple choice question HELPPP!!!??

Bas_tet [7]

Answer:

24/30

Step-by-step explanation:

5 0

2 years ago

Oblicz.Pamiętaj o kolejności wykonywania działań

SashulF [63]

Answer:

33.275

Step-by-step explanation:

1 step: Difference in brackets

$3.5-2\dfrac{1}{3}=3\dfrac{1}{2}-2\dfrac{1}{3}=(3-2)+\left(\dfrac{1}{2}-\dfrac{1}{3}\right)=1+\dfrac{3-2}{3\cdot 2}=1+\dfrac{1}{6}=1\dfrac{1}{6}$

2 step: $0.75\div\dfrac{1}{3}$

$0.75\div\dfrac{1}{3}=\dfrac{75}{100}\div \dfrac{1}{3}=\dfrac{3}{4}\times \dfrac{3}{1}=\dfrac{9}{4}$

3 step: $1.28\div 0.04$

$1.28\div 0.04=128\div 4=32 \ \text{Move point two decimal places}$

4 step:

$2\dfrac{1}{4}\times 1\dfrac{1}{6}=\dfrac{2\cdot 4+1}{4}\times \dfrac{1\cdot 6+1}{6}=\dfrac{9}{4}\times \dfrac{7}{6}=\dfrac{63}{24}=\dfrac{21}{8}$

5 step:

$\dfrac{9}{4}+32-\dfrac{21}{8}+1.65=(32+1.65)+\left(\dfrac{9}{4}-\dfrac{21}{8}\right)=33.65+\dfrac{9\cdot 2-21}{8}=33.65-\dfrac{3}{8}=33.65-0.375=33.275$

6 0

2 years ago

Joe works as a busboy making $7 per hour and as a theater usher making $9 per hour. Let b be the number of hours he works as a b

Vilka [71]

Answer:

The inequality describing the situation is:

$7b+9u>1500$

Step-by-step explanation:

Joe works as a busboy at the rate of = $7 per hour

Let the number of hours he works as a bus boy this month be = $b$ hours

∴ Amount Joe would make this month working as a busboy = $\$7\times b=\$7b$

Joe works as a theater usher at the rate of = $9 per hour

Let the number of hours he works as a theater usher this month be = $u$ hours

∴ Amount Joe would make this month working as a theater usher = $\$9\times u=\$9u$

Total amount Joe would make this month = $\$(7b+9u)$

His goal is earn more than $1500 this month.

∴ The situation can be represented in the following inequality:

$7b+9u>1500$

6 0

2 years ago

The lifespan (in days) of the common housefly is best modeled using a normal curve having mean 22 days and standard deviation 5.

Natasha_Volkova [10]

Answer:

Yes, it would be unusual.

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 normally distributed samples are solved using the z-score formula.

In a set with mean $\mu$ and standard deviation $\sigma$ , the zscore 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 pvalue, we get the probability that the value of the measure is greater than X.

If $Z \leq -2$ or $Z \geq 2$ , the outcome X is considered unusual.

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 $s = \frac{\sigma}{\sqrt{n}}$ .