If 20 shirts cost $100, how many shirts can i buy for $300 ?*

Mathematics

2 answers:

Liono4ka [1.6K]3 years ago

4 0

Answer:

You can buy 60 shirts

Step-by-step explanation:

20 = 100$

40 = 200$

60 = 300$

GalinKa [24]3 years ago

3 0

Answer:

Step-by-step explanation:

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Use the F-scale measurements of tornadoes listed in the accompanying table. The range of the data is 4.0. Use the range rule of

Tcecarenko [31]

Answer:

Within 0.5 of ;

is not ;

Step-by-step explanation:

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;

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The Information Technology Department at a large university wishes to estimate the proportion of students living in the dormitor

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Answer:

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Step-by-step explanation:

Previous concepts

A confidence interval is "a range of values that’s likely to include a population value with a certain degree of confidence. It is often expressed a % whereby a population means lies between an upper and lower interval".

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Solution to the problem

In order to find the critical value we need to take in count that we are finding the interval for a proportion, so on this case we need to use the z distribution. Since our interval is at 99% of confidence, our significance level would be given by $\alpha=1-0.99=0.01$ and $\alpha/2 =0.005$ . And the critical value would be given by: