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3 years ago

I need to figure out how to answer this.

Mathematics

1 answer:

oksian1 [2.3K]3 years ago

7 0

For 7 to 9, substitute each answer in to the two equations.

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Find the LCM for 6 and 4.

DENIUS [597]

The LCM of 6 and 4, is 12.

5 0

2 years ago

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Damon borrowed money from his grandmother 3 years ago and agreed to pay her 4% simple annual interest. At the end of 3 years, he

sergeinik [125]

Answer:

200

Step-by-step explanation:

200×4%=8

8×3=24

The original amount is $200

6 0

3 years ago

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A set of test scores is normally distributed with a mean of 130 and a standard deviation of 30 What score is necessary to reach

nlexa [21]

Answer:

A score of 150.25 is necessary to reach the 75th percentile.

Step-by-step explanation:

Problems of normal distributions can be 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.

A set of test scores is normally distributed with a mean of 130 and a standard deviation of 30.

This means that $\mu = 130, \sigma = 30$

What score is necessary to reach the 75th percentile?

This is X when Z has a pvalue of 0.75, so X when Z = 0.675.

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

$0.675 = \frac{X - 130}{30}$

$X - 130 = 0.675*30$

$X = 150.25$

A score of 150.25 is necessary to reach the 75th percentile.

7 0

3 years ago

A migrating bird flies 700 miles in 1414 hours. How many miles does it fly in 33 hours

Lisa [10]

In 1414 hours it covered 700 miles

In 1 hour it would have covered (700/1414) mile

In 33 hours it will then cover : 700/1414 * 33 = 16.34

So in 33 hours it will cover ≈ 16.34 miles.

5 0

2 years ago

Pine Lane Middle School's student council has 10 seventh graders and 8 eighth graders serving as representatives. A subcommittee

Nikitich [7]

Hey there! I'm happy to help!

When dealing with picking things and finding the number of possibilities, we can be dealing with two different types of things: permutations or combinations. We use permutations when order is important to the groups and we use combinations if order is not important.

It appears here that order is not important here as the subcommittee doesn't have to be in a specific order, so we will be using combinations.

So, we have ten seventh graders to choose from. Then we will have 9, and then 8. So, we multiply these numbers of choices.

10×9×8=720

Now, we need to divide by 6. This is to show that order doesn't matter. Why? Because there are 6 possible ways to organize 3 seats on the committee (3×2×1), and we want to divide out all of the different orders so it is just the specific group of people and not their different organizations that are counted.

720/6=120

Now, we need to find this with the eighth graders.

8×7×6=336

And we divide by the number of seats factorial (3 seats for the eighth graders, so 3×2×1=6 again)

336/6=56

Now, we multiply our numbers for seventh and eighth graders to find all off the possibilities.

120×56=6720

So, there are 6720 subcommittees possible.

Have a wonderful day and keep on learning! :D

6 0

2 years ago