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3 years ago

PLEASE HELP SO I CAN GO EAT LUNCH!!

Mathematics

1 answer:

DENIUS [597]3 years ago

8 0

Answer:

Average low temp. = 6. The fourth number is 9.

Step-by-step explanation:

To find the average of 7 low temperatures, add them and divide the sum by 7.

Average low temp. = (5 + 8 + 6 + 5 + 10 + 7 + 1) / 7 = 42 / 7 = 6

The mean is the average. Call the missing number x.

There are four numbers, three of which are given. Add all the number, including the unknown x, then divide the sum by 4. The result is 7 (given in the problem).

$\frac{5+7+7+x}{4}=7\\\frac{19+x}{4}=7\\19+x=28\\x=9$

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You need to find the GCF of 256 and 400 Would you rather list their factors or use the prime factorization

trasher [3.6K]

If you were looking for the greatest common factor, you'd want to see the list of their factors.

A prime factorization breaks it down as far as possible and as a result has as few high numbers as possible. If you want the number to be as great as possible, you would want to see the list of all the factors.

4 0

3 years ago

Read 2 more answers

The net weights (in grams) of a sample of bottles filled by a machine manufactured by Edne, and the net weights of a sample fill

Andru [333]

Answer:

Since is a right tailed test we need to look on the t distribution with 12 degrees of freedom that accumulates 0.05 of the area on the right. And we can use the following excel code:

"=T.INV(0.95,12)" and we got $t_{crit}=+1.782$

Step-by-step explanation:

When we have two independent samples from two normal distributions with equal variances we are assuming that

$\sigma^2_1 =\sigma^2_2 =\sigma^2$

And the statistic is given by this formula:

$t=\frac{(\bar X_1 -\bar X_2)-(\mu_{1}-\mu_2)}{S_p\sqrt{\frac{1}{n_1}+\frac{1}{n_2}}}$

Where t follows a t distribution with $n_1+n_2 -2$ degrees of freedom and the pooled variance $S^2_p$ is given by this formula:

$\S^2_p =\frac{(n_1-1)S^2_1 +(n_2 -1)S^2_2}{n_1 +n_2 -2}$

This last one is an unbiased estimator of the common variance $\sigma^2$

The system of hypothesis on this case are:

Null hypothesis: $\mu_O \leq \mu_E$

Alternative hypothesis: $\mu_O > \mu_E$

Or equivalently:

Null hypothesis: $\mu_O - \mu_E \leq 0$

Alternative hypothesis: $\mu_O -\mu_E > 0$

Our notation on this case :

$n_E =6$ represent the sample size for group Edne

$n_O =8$ represent the sample size for group Orno

$\bar X_E =7$ represent the sample mean for the group Edne

$\bar X_O =10$ represent the sample mean for the group Orno

$s_E=1.414$ represent the sample standard deviation for group Edne

$s_O=2.268$ represent the sample standard deviation for group Orno

First we can begin finding the pooled variance:

$\S^2_p =\frac{(6-1)(1.414)^2 +(8 -1)(2.268)^2}{6 +8 -2}=3.834$

And the deviation would be just the square root of the variance:

$S_p=1.958$

And now we can calculate the statistic:

$t=\frac{(10 -7)-(0)}{1.958\sqrt{\frac{1}{6}+\frac{1}{8}}}=2.837$

Now we can calculate the degrees of freedom given by:

$df=6+8-2=12$

Since is a right tailed test we need to look on the t distribution with 12 degrees of freedom that accumulates 0.05 of the area on the right. And we can use the following excel code:

"=T.INV(0.95,12)" and we got $t_{crit}=+1.782$

Since our calculated value is higher than the critical value we have anough evidence to reject the null hypothesis, and on thsi case the mean for Orno is significanlty higher than the mean for Edne at 5% of significance.

4 0

3 years ago

According to the World Health Organization (WHO) Child Growth Standards, the head circumference for boys at birth is normally di

mars1129 [50]

Answer: the z score is 1

Step-by-step explanation:

Since the head circumference for boys at birth is normally distributed,

we would apply the formula for normal distribution which is expressed as

z = (x - µ)/σ

Where

x = head circumference for boys at birth.

µ = mean head circumference

σ = standard deviation

From the information given,

µ = 34.5cm

σ = 1.3 cm

For a boy born with a head circumference of 35.8cm, the z score is

z = (35.8 - 34.5)/1.3

z = 1

7 0

3 years ago

Which expression is equal to 5^4x5^85

Serga [27]

Answer:

5^89

Step-by-step explanation:

7 0

3 years ago

Please help me <br> What should I do ?

likoan [24]

Im not sure but i need points :( i’m sorry that i is the answer correct

8 0

3 years ago

Read 2 more answers