What is 80% of 400 please help me

Lee wants to buy two pairs of shoes. One pair costs $37.07 and the other pair costs $42.48. A pair of socks cost $8.50. If Lee b

daser333 [38]

Answer:

$96.55

Step-by-step explanation:

The computation of the money he would require is shown below:

Since lee wants to buy both pairs of shoes and the two pairs of socks

So the amount of money he needed is

= $37.07 + $42.48 + 2 × $8.50

= $37.07 + $42.48 + $17

= $96.55

5 0

3 years ago

James is x years old now and the sum of his age is and his brothers age is 10.

Vesnalui [34]

Answer:

1) James brother is 10-x years old

2) James was 3 years ago x-3 years old

3) James brother was 3 years ago 7-x years old

4) 3(x-3)=7-x

5) James is 4 years old, his brother is 6 years old

Step-by-step explanation:

3) 10 - x - 3 = 7 - x

5) 3* James age 3 years ago = James brothers age 3 years ago

<=> 3*(x-3) = 7-x

<=> 3x - 9 = 7 - x

<=> 4x = 16

<=> x = 4

5 0

3 years ago

What is the value of p?

kenny6666 [7]

Answer:

35

Step-by-step explanation:

All angles of a triangle add up to 180 degrees, so you can add the other two angles, then subtract by 180.

4 0

3 years ago

Read 2 more answers

The mayor of a town has proposed a plan for the annexation of a new bridge. A political study took a sample of 1000 voters in th

garri49 [273]

Answer:

$z=\frac{0.42 -0.39}{\sqrt{\frac{0.39(1-0.39)}{1000}}}=1.945$

$p_v =P(Z>1.945)=0.0259$

If we compare the p value obtained with the significance level given $\alpha=0.02$ we have $p_v>\alpha$ so we can conclude that we have enough evidence to FAIL to reject the null hypothesis, and we can said that at 2% of significance the proportion of residents who favored annexation is not significantly higher than 0.39.

Step-by-step explanation:

1) Data given and notation

n=1000 represent the random sample taken

$\hat p=0.42$ estimated proportion of residents who favored annexation

$p_o=0.39$ is the value that we want to test

$\alpha=0.02$ represent the significance level

Confidence=98% or 0.98

z would represent the statistic (variable of interest)

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

2) Concepts and formulas to use

We need to conduct a hypothesis in order to test the claim that the proportion is higher than 0.39:

Null hypothesis: $p\leq 0.39$

Alternative hypothesis: $p > 0.39$

When we conduct a proportion test we need to use the z statistic, and the is given by:

$z=\frac{\hat p -p_o}{\sqrt{\frac{p_o (1-p_o)}{n}}}$ (1)

The One-Sample Proportion Test is used to assess whether a population proportion $\hat p$ is significantly different from a hypothesized value $p_o$ .

3) Calculate the statistic

Since we have all the info requires we can replace in formula (1) like this:

$z=\frac{0.42 -0.39}{\sqrt{\frac{0.39(1-0.39)}{1000}}}=1.945$

4) Statistical decision

It's important to refresh the p value method or p value approach . "This method is about determining "likely" or "unlikely" by determining the probability assuming the null hypothesis were true of observing a more extreme test statistic in the direction of the alternative hypothesis than the one observed". Or in other words is just a method to have an statistical decision to fail to reject or reject the null hypothesis.

The significance level provided $\alpha=0.02$ . The next step would be calculate the p value for this test.

Since is a right tailed test the p value would be:

$p_v =P(Z>1.945)=0.0259$

If we compare the p value obtained with the significance level given $\alpha=0.02$ we have $p_v>\alpha$ so we can conclude that we have enough evidence to FAIL to reject the null hypothesis, and we can said that at 2% of significance the proportion of residents who favored annexation is not significantly higher than 0.39.

4 0

3 years ago

F(1)=-8<br> f(n)=f(n-1)-3<br> Find the explicit formula<br> Will mark Brainiest

laiz [17]

f(1) = -8, simply is a way of saying, the 1st value in the arithmetic sequence is -8.

f(n) = f(n-1) - 3, is another way of saying, following values are just, the previous minus -3.

so in short, -3 is the common difference, since that is what we're "adding" to get the new value in the sequence.

$\bf n^{th}\textit{ term of an arithmetic sequence} \\\\ a_n=a_1+(n-1)d\qquad \begin{cases} a_n=n^{th}\ term\\ n=\textit{term position}\\ a_1=\textit{first term}\\ d=\textit{common difference}\\[-0.5em] \hrulefill\\ d = -3\\ a_1 = -8 \end{cases} \\\\\\ a_n=-8+(n-1)(-3)\implies a_n=-8-3n+3\implies \stackrel{f(n)}{a_n}=\stackrel{\stackrel{explicit}{\downarrow }}{-3n-5}$

6 0

3 years ago