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3 years ago

Level B

1 answer:

5 0

The number has 2 digits - let's call them x and y. The positive difference between the two combinations (lowest-highest and highest-lowest) is always equal to the positive difference of x and y, multiplied by 9.

For example:

76 and 67: 76 - 67 = 9 and ((7-6)*9) = 1*9 = 9
73 and 37: 73 - 37 = 36 and ((7-3)*9) = 4*9 = 36

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Answer:

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3 years ago

76.00 km = ft?<br><br><br><br> Please someone help me

kifflom [539]

Answer:

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3 years ago

Read 2 more answers

The following are the ages (years) of 5 people in a room:

MA_775_DIABLO [31]

Answer:

The person is 14 years old

Step-by-step explanation:

1. Multiply 6 times 18 which is 108

2. Add all numbers together in list which is 94

3. Subtract 94 from 108 which is 14

4. To check answer add 94 plus 14 and divide by 6 and you will get the median which is 18, now you know this answer is correct.

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3 years ago

Statisticians use ______ scores to divide the ______ under a curve the way people use a knife to cut pizza. Just as the pizza is

solong [7]

Answer:

Statisticians use z-scores to divide the area under a curve the way people use a knife to cut pizza.

Step-by-step explanation:

Statisticians use z-scores to divide the area under a curve the way people use a knife to cut pizza.

z-score:

A z-score is a numerical measurement which is measured in terms of standard deviations from the mean.
Formula:

$z_{score} = \displaystyle\frac{x-\mu}{\sigma}$

If a z-score is 0, it tells that the data point is same as the mean.
Area under the normal curve is 1.

6 0

3 years ago

A storage tank will have a circular base of radius r and a height of r. The tank can be either cylindrical or hemispherical (ha

Neko [114]

Answer:

Volume: $\frac{2}{3}\pi r^3$

Ratio: $\frac{2}{9}r$

Step-by-step explanation:

First of all, we need to find the volume of the hemispherical tank.

The volume of a sphere is given by:

$V=\frac{4}{3}\pi r^3$

where

r is the radius of the sphere

V is the volume

Here, we have a hemispherical tank: a hemisphere is exactly a sphere cut in a half, so its volume is half that of the sphere:

$V'=\frac{V}{2}=\frac{\frac{4}{3}\pi r^3}{2}=\frac{2}{3}\pi r^3$

Now we want to find the ratio between the volume of the hemisphere and its surface area.

The surface area of a sphere is

$A=4 \pi r^2$

For a hemisphere, the area of the curved part of the surface is therefore half of this value, so $2\pi r^2$ . Moreover, we have to add the surface of the base, which is $\pi r^2$ . So the total surface area of the hemispherical tank is

$A'=2\pi r^2 + \pi r^2 = 3 \pi r^2$

Therefore, the ratio betwen the volume and the surface area of the hemisphere is

$\frac{V'}{A'}=\frac{\frac{2}{3}\pi r^3}{3\pi r^2}=\frac{2}{9}r$

6 0

3 years ago