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3 years ago

Cot y, if csc y =-10/3 and cos y< 0

1 answer:

7 0

$\csc y=-\dfrac{10}3\implies\sin y=-\dfrac3{10}$

$\cos^2y=1-\sin^2y\implies \cos y=\pm\sqrt{1-\dfrac9{100}}=\pm\dfrac{\sqrt{91}}{10}$

You're told that $\cos y$ , so omit the positive root.

$\cot y=\dfrac{\cos y}{\sin y}=\dfrac{-\frac{\sqrt{91}}{10}}{-\frac3{10}}=\dfrac{\sqrt{91}}3$

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An employee earns a gross pay of $1,200.00 per week. The employee's net pay is $850.00. The employee's voluntary 401(k) contribu

Yuliya22 [10]

Answer:

$300 was deducted from tax. The tax rate is 26.1%

Step-by-step explanation:

An employee earns a gross pay of $1,200.00 per week. The employee’s net pay is $850.00. The employee’s voluntary 401(k) contribution is $50.00 per month.

There was blank deducted for taxes. The tax rate is blank

Solution:

Contributions that are made for retirement such as 401(k) contribution plans are made on a pretax basis. This means that they are removed from your taxable income, thereby reducing the tax.

Gross pay = $1200

Taxable income = Gross pay - 401(k) contribution

Taxable income = $1200 - $50 = $1150

Net pay = $850

Tax = Taxable income - Net pay

Tax = $1150 - $850

Tax = $300

Tax rate = (Tax / taxable income) * 100%

Tax rate = ($300 / $1150) * 100% = 26.1%

3 0

2 years ago

The owner of an orange grove estimates that if 24 trees are planted per acre, then each mature tree will yield 600 oranges per y

tia_tia [17]

Answer:

16428 oranges

Explanation:

Total yield = number of trees × number of oranges in each tree

Initial yield = 600×24= 14400 oranges

To find the equation needed, let x = additional trees and y= total yield

Number of trees = 24 +x

Number of oranges in each tree = 600-12x

Equation of total yield y= (24+x)(600-12x)

y= 14400-288x+600x-12x²

y= -12x²+312x+14400

Using a graphing calculator, from the graph drawn for this quadratic equation, we notice that it is a parabola. Therefore to find the maximum value, we should find the maximum point which is at the vertex of the parabola, we use the formula x= -b/2a

A quadratic equation is such: ax²+bx+c

Therefore x =-312/2×-12

x= -312/-24

x= 13

So we can conclude that in order to maximise oranges from the trees, the person needs to plant an additional 13 trees. Substituting from the above:

24+x=24+13= 37 trees in total

y= -12x²+312x+14400= -12×13²+312×13+14400= -2028+4056+14400

=16428 oranges in total yield

8 0

2 years ago

Laura makes 10.5% commission on each of her sales. How much does she make when she sells a house for 85,000

kykrilka [37]

Answer:

85000/100*10.5 = $8925

Step-by-step explanation:

N/A

5 0

2 years ago

A fast food restaurant executive wishes to know how many fast food meals teenagers eat each week. They want to construct a 99% c

Lana71 [14]

Answer:

The minimum sample size required to create the specified confidence interval is 2229.

Step-by-step explanation:

We have that to find our $\alpha$ level, that is the subtraction of 1 by the confidence interval divided by 2. So:

$\alpha = \frac{1-0.99}{2} = 0.005$

Now, we have to find z in the Ztable as such z has a pvalue of $1-\alpha$ .

So it is z with a pvalue of $1-0.005 = 0.995$ , so $z = 2.575$

Now, find the margin of error M as such

$M = z*\frac{\sigma}{\sqrt{n}}$

In which $\sigma$ is the standard deviation of the population and n is the size of the sample.

What is the minimum sample size required to create the specified confidence interval

This is n when $M = 0.06, \sigma = 1.1$

$0.06 = 2.575*\frac{1.1}{\sqrt{n}}$

$0.06\sqrt{n} = 2.575*1.1$

$\sqrt{n} = \frac{2.575*1.1}{0.06}$

$(\sqrt{n})^{2} = (\frac{2.575*1.1}{0.06})^{2}$

$n = 2228.6$

Rounding up

The minimum sample size required to create the specified confidence interval is 2229.

7 0

3 years ago

How long will it take to have R30 000 for a trip to Europe if I invest R20 000 now at 15% per year, compounded quarterly?

maw [93]

Compound interest formula

$A=P(1+ \frac{r}{n} )^{nt}$

Where

A= Future value
P = the Principal (the initial amount of money)
r = annual interest rate

t = time

n= number of times compounded in one t

Remark
----------------------------------------------------------------------------------

r is generally a percentage like 3%, 7% etc and are applied in the formula as 0.03, 0.07...,

the interest is compounded generally annually (n=1), quarterly (n=4), monthly (n=12), etc...

t is in years,

In our problem:

A= 30 000

P =20 000

r = 15%=0.15

time = t = ?

n= 4

applying the formula:

$A=P(1+ \frac{r}{n} )^{nt}\\\\30,000=20,000(1+ \frac{0.15}{4} )^{4t}\\\\ \displaystyle{\frac{30,000}{20,000} =(1.0375)^{4t}$

$\displaystyle{ 1.5={(1.0375^4)}^t\\\\$

$1.5=1.159^t\\\\ \displaystyle { t=log_{1.159}1.5=2.75$

75% of 12 months is 3/4 of 12 months, which is 9 months

Answer: 2 years, 9 months

3 0

3 years ago