A=v1-v0/t solve for v1

What is a formula for the nth term of the given sequence?<br> 20,50, 125...

loris [4]

Answer:

a(n) = 20*2.5^(n - 1)

Step-by-step explanation:

Note that 50 is 2.5 times 20, and that 125 is 2.5 times 50. Thus the common factor is 2.5. The formula for the nth term is

a(n) = a(1)*r^(n - 1) => a(n) = 20*2.5^(n - 1)

3 0

3 years ago

The temperature in Fargo North Dakota was 6°F at noon. By 4 PM the temperature dropped to -10°F. What integer represents the cha

tiny-mole [99]

The change expressed as an integer is -16.

5 0

3 years ago

Each of 16 store cashiers worked an average of 21 hours per week and are paid $8.25 per hour. After the store manager hires 2 ad

Pachacha [2.7K]

Answer:

Step-by-step explanation:

Initially:

21 hours per week at 8.25 per hours means:

21 * 8.25 = 173.25 dollars per person

16 person = 16 * 173.25 = $2772 (total)

2nd phase:

2 more cashier = 16 + 2 = 18 cashiers

Per hour 0.25 more, so 8.25 + 0.25 = $8.50 per hour

1.5 hrs less than 21, so 21 - 1.5 = 19.5 hours

Hence,

18 * 19.5 * 8.50 = $2983.50 (new total)

Change in money paid = 2983.50 - 2772 = $211.50

4 0

3 years ago

Based on an indication that mean daily car rental rates may be higher for Boston than for Dallas, a survey of eight car rental c

Elina [12.6K]

Answer:

$t=\frac{(47 -44)-(0)}{3\sqrt{\frac{1}{8}+\frac{1}{9}}}=2.058$

The degrees of freedom are:

$df=8+9-2=15$

And the p value would be:

$p_v =P(t_{15}>2.058) =0.0287$

Since we have a p value lower than the significance level given of 0.05 we can reject the null hypothesis and we can conclude that the true mean for car rental rates in Boston are signiﬁcantly higher than those in Dallas

Step-by-step explanation:

Data given

$n_1 =8$ represent the sample size for group Boston

$n_2 =9$ represent the sample size for group Dallas

$\bar X_1 =47$ represent the sample mean for the group Boston

$\bar X_2 =44$ represent the sample mean for the group Dallas

$s_1=3$ represent the sample standard deviation for group Boston

$s_2=3$ represent the sample standard deviation for group Dallas

We can assume that we have independent samples from two normal distributions with equal variances and that is:

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

Let the subindex 1 for Boston and 2 for Dallas we want to check the following hypothesis:

Null hypothesis: $\mu_1 \leq \mu_2$

Alternative hypothesis: $\mu_1 > \mu_2$

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

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

Replacing we got:

$\S^2_p =\frac{(8-1)(3)^2 +(9 -1)(3)^2}{8 +9 -2}=9$

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

$S_p=3$

The statitsic would be:

$t=\frac{(47 -44)-(0)}{3\sqrt{\frac{1}{8}+\frac{1}{9}}}=2.058$

The degrees of freedom are:

$df=8+9-2=15$

And the p value would be:

$p_v =P(t_{15}>2.058) =0.0287$

Since we have a p value lower than the significance level given of 0.05 we can reject the null hypothesis and we can conclude that the true mean for car rental rates in Boston are signiﬁcantly higher than those in Dallas

5 0

3 years ago

Dorothy and Rosanne are baking cookies for a party. Working alone, Rosanne can finish the cookies in 6 hours. Dorothy can finish

garik1379 [7]

Answer:

It will take them 3.43 hours.

Step-by-step explanation:

Let T denote the total cookies that need to be cocked. Observe that:

If Rosanne finishes the cookies in 6 hours, that means that she can make $\frac{T}{6}$ cookies per hour.
If Dorothy finishes the cookies in 8 hours, that means that she can make $\frac{T}{8}$ cookies per hour.

Then, by 1) and 2), if they work together would we able to make

$\frac{T}{6}+\frac{T}{8}=\frac{8T+6T}{48}=\frac{14}{48}T=\frac{7}{24}T$

cookies per hour.

Therefore, in order to finish the T cookies they will need $\frac{24}{7}\approx3.43 hours$

3 0

3 years ago