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3 years ago

5

the combined weight of an older sister and her baby brother is 74 pounds. The weight of the older sister is 2 pounds less than t

hree times the baby brothers weight. Write and solve a linear equation that will find the weight of each sibling.

1 answer:

Naddik [55]3 years ago

7 0

74-2=72 and 72 times 3=216 that willl be your answer

You might be interested in

What is x when 5(2x+1)=10x

Gnoma [55]

Step-by-step explanation:

1.before starting first collect the like terms.

5(2x+1)=10x

the like terms are 10x and 2x

2. 5+1=10x-2x because the 2x us crosing the equality sign

that is

6=8

5 0

2 years ago

In 1998 the average income for middle class families in the US was $37,100 with a population standard deviation of $6362. We wan

sammy [17]

Answer:

Since we know the population deviation, is better apply a z test to compare the actual mean to the reference value, and the statistic is given by:

$z=\frac{\bar X-\mu_o}{\frac{\sigma}{\sqrt{n}}}$ (1)

z-test: "Is used to compare group means. Is one of the most common tests and is used to determine if the mean is (higher, less or not equal) to an specified value".

The best answer would be:

A. Z test

Step-by-step explanation:

Data given and notation

$\bar X=36670$ represent the mean average

$\sigma=6362$ represent the population standard deviation for the sample

$n=1225$ sample size

$\mu_o =37100$ represent the value that we want to test

$\alpha$ represent the significance level for the hypothesis test.

z would represent the statistic (variable of interest)

$p_v$ represent the p value for the test (variable of interest)

State the null and alternative hypotheses.

We need to conduct a hypothesis in order to check if the mean is equal or not to 37100, the system of hypothesis would be:

Null hypothesis: $\mu =37100$

Alternative hypothesis: $\mu \neq 37100$

Since we know the population deviation, is better apply a z test to compare the actual mean to the reference value, and the statistic is given by:

$z=\frac{\bar X-\mu_o}{\frac{\sigma}{\sqrt{n}}}$ (1)

z-test: "Is used to compare group means. Is one of the most common tests and is used to determine if the mean is (higher, less or not equal) to an specified value".

The best answer would be:

A. Z test

5 0

3 years ago

Which of the following polygons has nine lines of symmetry?

anastassius [24]

So we know d. is out and that's all I got help wise sorry its not much..:)

3 0

3 years ago

Read 2 more answers

What is the minimum force required to prevent a ball weighing 22.6 lb from rolling down a ramp which is inclined at 39.0 degrees

Alona [7]

The correct answer is 14.2 lb which is choice D.

Let:

F = minimum force required to prevent ball from rolling down the ramp

The formula will be:

F = w * sin theta

F = w * sin (39 degrees)

F = 22.6 * sin (39)
= 14.2 lb (this is rounded to the nearest tenth)

7 0

3 years ago

According to an article, 47% of adults have experienced a breakup at least once during the last 10 years. Of 9 randomly select

In-s [12.5K]

Answer:

a) $P(X=5)=(9C5)(0.47)^5 (1-0.47)^{9-5}=0.228$

b) $P(X=0)=(9C0)(0.47)^0 (1-0.47)^{9-0}=0.0033$

And replacing we got:

$P(X \geq 1)= 1-P(X$

c) $P(X=4)=(9C4)(0.47)^4 (1-0.47)^{9-4}=0.257$

$P(X=5)=(9C5)(0.47)^5 (1-0.47)^{9-5}=0.228$

$P(X=6)=(9C6)(0.47)^6 (1-0.47)^{9-6}=0.135$

And adding we got:

$P(4 \leq X \leq 6)= 0.257+0.228+0.135=0.620$

Step-by-step explanation:

Previous concepts

The binomial distribution is a "DISCRETE probability distribution that summarizes the probability that a value will take one of two independent values under a given set of parameters. The assumptions for the binomial distribution are that there is only one outcome for each trial, each trial has the same probability of success, and each trial is mutually exclusive, or independent of each other".

Solution to the problem

Let X the random variable of interest, on this case we now that:

$X \sim Binom(n=9, p=0.47)$

The probability mass function for the Binomial distribution is given as:

$P(X)=(nCx)(p)^x (1-p)^{n-x}$

Where (nCx) means combinatory and it's given by this formula:

$nCx=\frac{n!}{(n-x)! x!}$

Assuming the following questions:

a. exactly five

For this case we can use the probability mass function and we got:

$P(X=5)=(9C5)(0.47)^5 (1-0.47)^{9-5}=0.228$

b. at least one

For this case we want this probability:

$P(X \geq 1)$

And we can use the complement rule and we got:

$P(X \geq 1)= 1-P(X$

$P(X=0)=(9C0)(0.47)^0 (1-0.47)^{9-0}=0.0033$

And replacing we got:

$P(X \geq 1)= 1-P(X$

c. between four and six, inclusive.

For this case we want this probability:

$P(4 \leq X \leq 6)$

$P(X=4)=(9C4)(0.47)^4 (1-0.47)^{9-4}=0.257$

$P(X=5)=(9C5)(0.47)^5 (1-0.47)^{9-5}=0.228$

$P(X=6)=(9C6)(0.47)^6 (1-0.47)^{9-6}=0.135$

And adding we got:

$P(4 \leq X \leq 6)= 0.257+0.228+0.135=0.620$

6 0

3 years ago