Whats 1 + 1? Im very confused

Anchara drops a penny from a height of 60 feet above the ground. The equation h=-16t^2 + 60 models the penbys height h i feet as

weeeeeb [17]

Answer:

t = 1.94 seconds

Step-by-step explanation:

we have to solve the following polynomial equation:

-16t² + 60 = 0

16t² = 60

t² = 60/16 = 3.75

t = √3.75 = 1.936491673 seconds

the equation also has another possible answer = -1.936491673 seconds, but since time cannot be negative, we have to dismiss that option

7 0

3 years ago

1. Alexa drove 5 miles from home to school. Then, taking a different route, she drove 4 3/5 miles back home. What was the total

jenyasd209 [6]

Answer:

5x4 3/5=23

Step-by-step explanation:

take the 5 miles from home to school then basically you do it 4 and 3/5 more times so just multiply.

3 0

3 years ago

A random sample of 49 measurements from one population had a sample mean of 15, with sample standard deviation 5. An independent

kotykmax [81]

Answer:

Comparing the p value with the significance level $\alpha=0.01$ we see that $p_v$ so we can conclude that we have enough evidence to reject the null hypothesis, and the difference between the two groups is significantly different.

Step-by-step explanation:

$\bar X_{1}=15$ represent the mean for sample 1

$\bar X_{2}=18$ represent the mean for sample 2

$s_{1}=5$ represent the sample standard deviation for 1

$s_{f}=6$ represent the sample standard deviation for 2

$n_{1}=49$ sample size for the group 2

$n_{2}=64$ sample size for the group 2

$\alpha=0.01$ Significance level provided

t would represent the statistic (variable of interest)

Concepts and formulas to use

We need to conduct a hypothesis in order to check if the difference in the population means, the system of hypothesis would be:

Null hypothesis: $\mu_{1}-\mu_{2}=0$

Alternative hypothesis: $\mu_{1} - \mu_{2}\neq 0$

We don't have the population standard deviation's, so for this case is better apply a t test to compare means, and the statistic is given by:

$t=\frac{(\bar X_{1}-\bar X_{2})-\Delta}{\sqrt{\frac{s^2_{1}}{n_{1}}+\frac{s^2_{2}}{n_{2}}}}$ (1)

And the degrees of freedom are given by $df=n_1 +n_2 -2=49+64-2=111$

t-test: Is used to compare group means. Is one of the most common tests and is used to determine whether the means of two groups are equal to each other.

With the info given we can replace in formula (1) like this:

$t=\frac{(15-18)-0}{\sqrt{\frac{5^2}{49}+\frac{6^2}{64}}}}=-2.897$

P value

Since is a bilateral test the p value would be:

$p_v =2*P(t_{111}$

Comparing the p value with the significance level $\alpha=0.01$ we see that $p_v$ so we can conclude that we have enough evidence to reject the null hypothesis, and the difference between the two groups is significantly different.

7 0

3 years ago

I need help, the question is “What is the slope, m, and y-intercept for the line that is plotted on the grid below?”

vlabodo [156]

Answer:

m = 2, (0,4)

Step-by-step explanation:

Slope is 2

Y intercept is 0,4

3 0

3 years ago

On a winter morning, the temperature before sunrise was -10℉. The temperature then rose by 1℉ each hour for 7 hours before dropp

Artemon [7]

Answer:

The temperature after 10 hours is -9 ºF.

Step-by-step explanation:

This statement can be translated mathematically as follows. The temperature after 10 hours from sunrise is:

$T = -10\,^{\circ}F + \left(1\,\frac{^{\circ}F}{h} \right)\cdot (7\,h)+ \left(-2\,\frac{^{\circ}F}{h} \right)\cdot (3\,h)$

$T = -9\,^{\circ}F$

The temperature after 10 hours is -9 ºF.

6 0

4 years ago