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2 years ago

Which statements are true about the rules of multiplication for signed numbers? Check all that apply.

Mathematics

2 answers:

weqwewe [10]2 years ago

7 0

Answer:

here I think this is the same question. Hop this helps!

galina1969 [7]2 years ago

6 0

The product of two negative integers is positive. (-a) *(-b) = ab True

The product of two integers with different signs is positive. (-a) (b) = -ab False

If two numbers are the same sign, then the product is positive.

a*b = ab -a * -b = ab True

The product of a positive and a negative is negative.

-a * b =- ab a * -b =- ab True

If the signs of two integers are different, then the product is positive.

-a * b =- ab a * -b =- ab False

You might be interested in

Write the equation of the circle with center (−1, −3) and (−7, −5) a point on the circle.

Pepsi [2]

So, we know the center is at -1, -3, hmmm what's the radius anyway?

well, the radius will be the distance from the center to any point on the circle, it just so happen that we know -7, -5 is on it, thus

$\bf ~~~~~~~~~~~~\textit{distance between 2 points}\\\\
\begin{array}{ccccccccc}
&&x_1&&y_1&&x_2&&y_2\\
% (a,b)
&&(~ -1 &,& -3~) 
% (c,d)
&&(~ -7 &,& -5~)
\end{array}
\\\\\\
d = \sqrt{( x_2- x_1)^2 + ( y_2- y_1)^2}
\\\\\\
r=\sqrt{[-7-(-1)]^2+[-5-(-3)]^2}\implies r=\sqrt{(-7+1)^2+(-5+3)^2}
\\\\\\
r=\sqrt{36+4}\implies r=\sqrt{40}\\\\
-------------------------------$

$\bf \textit{equation of a circle}\\\\ 
(x- h)^2+(y- k)^2= r^2
\qquad 
center~~(\stackrel{-1}{ h},\stackrel{-3}{ k})\qquad \qquad 
radius=\stackrel{\sqrt{40}}{ r}
\\\\\\\
[x-(-1)]^2+[y-(-3)]^2=(\sqrt{40})^2\implies (x+1)^2+(y+3)^2=40$

5 0

3 years ago

Suppose the weights of apples are normally distributed with a mean of 85 grams and a standard deviation of 8 grams. The weights

user100 [1]

Answer:

a) 0.0304 = 3.04% probability a randomly chosen apple exceeds 100 g in weight.

b) The weight that 80% of the apples exceed is of 78.28g.

Step-by-step explanation:

Normal Probability Distribution:

Problems of normal distributions can be solved using the z-score formula.

In a set with mean $\mu$ and standard deviation $\sigma$ , the z-score 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 p-value, we get the probability that the value of the measure is greater than X.

Weights of apples are normally distributed with a mean of 85 grams and a standard deviation of 8 grams.

This means that $\mu = 85, \sigma = 8$

a. Find the probability a randomly chosen apple exceeds 100 g in weight.

This is 1 subtracted by the p-value of Z when X = 100. So

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

$Z = \frac{100 - 85}{8}$

$Z = 1.875$

$Z = 1.875$ has a p-value of 0.9697

1 - 0.9696 = 0.0304

0.0304 = 3.04% probability a randomly chosen apple exceeds 100 g in weight.

b. What weight do 80% of the apples exceed?

This is the 100 - 80 = 20th percentile, which is X when Z has a p-value of 0.2, so X when Z = -0.84.

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

$-0.84 = \frac{X- 85}{8}$

$X - 85 = -0.84*8$

$X = 78.28$

The weight that 80% of the apples exceed is of 78.28g.

5 0

2 years ago

Wo numbers are in the ratio of 2 to 3. If the smaller number is 18, the larger number is

Zarrin [17]

The simplified ratio is 2:3. Since the smaller number when it's not simplified is 18, let's divide 18 by 2 to get our factor.
18/2 = 9.
So we can multiply 9 by 3 to get the missing larger number.
9 x 3 = 27.
Your missing number is 27, hope this helps!

5 0

3 years ago

Mr. Clark traveled 456.4 km in 14 days.

xeze [42]

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