Why is 210 divided by 30 the same as 21 tens divided by 3 tens

Mathematics

1 answer:

sveta [45]3 years ago

6 0

Answer:

It is by definition. 210 means 21 tens or 21 * 10. 30 means 3 tens or 3*10.

Since there is a ten on the top and bottom of the divisor 210/30 is also the same thing as 21/3. All of which is 7 and all of which is true by definition.

Step-by-step explanation:

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Answer:

The answer is B) 200mm. Check the image for the workings

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University dean is interested in determining the proportion of students who receive some sort offinancial aid. rather than exami

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The confidence interval is
$0.59\pm0.081$

We first find p, our sample proportion. 118/200 = 0.59.

Next we find the z-score associated with this level of confidence:
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Subtract from 1: 1-0.98 = 0.02
Divide by 2: 0.02/2 = 0.01
Subtract from 1: 1-0.01 = 0.99

Using a z-table (http://www.z-table.com) we see that this value is associated with a z-score of 2.33.

The margin of error (ME) is given by
$ME=z\sqrt{\frac{p(1-p)}{n}}
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4 years ago

Rachel has 60 scones. She sells them to Robbie, Cameron, Louis, Tom and Charlie in that order. Each customer buys more scones th

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Robbie bought the smallest amount. Let's use x for that amount.
Let's use n for amount that each following customer increases.

We have:
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Cameron=x+n
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Tom=x+n+n+n
Charlie=x+n+n+n+n

We know that they bought total of 60 scones.
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We are also given this information:
(Robbie + Cameron) = 3/7 * (Louis + Tom + Charlie)
We insert the equations from above:
(x + x+n) = 3/7 * (x+n+n + x+n+n+n + x+n+n+n+n)
2x + n = 3/7 * (3x + 9n) /*7
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x + 2n = 12
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x + 2n = 12
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Now we can solve for the amount for each customer.
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xxTIMURxx [149]

|2(-5) - 1| + 10
|-10-1| + 10
|-11| + 10
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Hope this helped!

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4 years ago

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