What does x equal if the equation is [x+3]÷2=9

Mathematics

1 answer:

ivanzaharov [21]3 years ago

7 0

The answer is 3 i think

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Help me find Sample variance and standard deviation

AnnZ [28]

First, find the mean. You'll need it to compute the variance.

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The variance of the sample is then computed with the formula

$s^2=\displaystyle\dfrac1{5-1}\sum_{i=1}^5(\bar x-x_i)^2=\dfrac{(21-11)^2+\cdots+(11-11)^2}4=\dfrac{71}2=35.5$

The standard deviation is the square root of the variance, so

$s=\sqrt{35.5}\approx5.958$

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A weightlifter holds a 1,700 N barbell 1 meter above the ground. One end of a 2-meter-long chain hangs from the center of the ba

masha68 [24]

In physics, work is equal to the product of force and distance, given that the direction of force is the same with the direction of the distance.

W = Fd

The total force is
F = 1,700 N + 500 N = 2,200 N
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W = (2,220 N)(2 m) = 4,400 N·m or 4,400 J

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3 years ago

Suppose an opaque jar contains 3 red marbles and 10 green marbles. The following exercise refers to the experiment of picking tw

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Answer:

$\frac{5}{13}$