I need help please, i need the answer now!

Ben has 90 in his saving account. He plans to deposit 36 per week to build his account balance

Gelneren [198K]

Answer:

he will increase his account balance by $20 a year

Step-by-step explanation:

7 0

3 years ago

Two researchers conducted a study in which two groups of students were asked to answer 42 trivia questions from a board game. Th

Verizon [17]

Answer:

$(21.9-19.8) -1.966\sqrt{\frac{3.4^2}{200} +\frac{3.5^2}{200}}= 1.422$

$(21.9-19.8) -1.966 \sqrt{\frac{3.4^2}{200} +\frac{3.5^2}{200}}= 2.778$

And we are 95% confident that the true difference means are between $1.422 \leq \mu_1 -\mu_2 \leq 2.778$

Step-by-step explanation:

We know the following info:

$\bar X_1 = 21.9$ sample mean for group 1

$\bar X_2 = 19.8$ sample mean for group 2

$s_1 = 3.4$ sample standard deviation for group 1

$s_2 = 3.5$ sample standard deviation for group 2

$n_1 = 200$ sample size group 1

$n_2 = 200$ sample size group 2

We want to find a confidence interval for the difference of means and the correct formula to do this is:

$(\bar X_1 -\bar X_2) \pm t_{\alpha/2} \sqrt{\frac{s^2_1}{n_1} +\frac{s^2_2}{n_2}}$

Now we just need to find the critical value. The confidence level is 0.95 then the significance is $1-0.95 =0.05$ and $\alpha/2 =0.025$ . The degrees of freedom are given by:

$df= n_1 +n_2 -2= 200+200-2= 398$

The critical value for this case would be : $t_{\alpha/2}=1.966$

And replacing into the confidence interval formula we got:

$(21.9-19.8) -1.966\sqrt{\frac{3.4^2}{200} +\frac{3.5^2}{200}}= 1.422$

$(21.9-19.8) -1.966 \sqrt{\frac{3.4^2}{200} +\frac{3.5^2}{200}}= 2.778$

And we are 95% confident that the true difference means are between $1.422 \leq \mu_1 -\mu_2 \leq 2.778$

5 0

3 years ago

Garrett found the slope of the values in the table: A 2-column table with 3 rows. Column 1 is labeled Years: x with entries 4, 8

kakasveta [241]

Answer:

B

Step-by-step explanation:

5 0

3 years ago

Read 2 more answers

If the mean of 5 positive integers is 15, what is the maximum possible difference between the largest and the smallest of these

Vikki [24]

Answer:

if the 5 numbers are different, the maximum difference is 64

Step-by-step explanation:

We have 5 positive (different) integers, a, b, c, d and e (suppose that are ordered from least to largest, so a is the smallest and b is the largest.

The mean will be:

M = (a + b + c + d + e)/5 = 15.

Now, if we want to find the largest difference between a and e, then we must first select the first 4 numbers as the smallest numbers possible, this is:

a = 1, b = 2, c = 3 and d = 4

M = (1 + 2 + 3 + 4 + d)/5 = 15

M = (10 + d)/5 = 15

10 + d = 15*5 = 75

d = 75 - 10 = 65

then the difference between a and d is = 65 - 1 = 64.

Now, if we take any of the first 4 numbers a little bit bigger, then we will see that the value of d must be smaller, and the difference between d and a will be smaller.

5 0

3 years ago

3+7(0.7+1.3)<br> What is the answer and how to solve it?

quester [9]

When you see this kind of question use « BODMAS »
1.Add the 2 digits which is 3+7=10
2.Add the digits inside which is 0.7+1.3=2
3.Add the inside and outside
3+7(0.7+1.3)
10(2)=20

5 0

2 years ago