Simplify.<br> 7x +84/(x + 12)(x+10)

Angelina_Jolie [31]

One meter is composed of approximately 3.28 feet. To convert a certain measure in feet to meter, divide the number by 3.28. From the given above, using dimensional analysis and the conversion factor,

(750 ft) x (1 m/ 3.28 ft) = 228.66 m

Thus, 750 ft is approximately 228.66 in meters.

6 0

3 years ago

The mean preparation fee H&R Block charged retail customers in 2012 was $183 (The Wall Street Journal, March 7, 2012). Use t

astraxan [27]

Answer:

a)0.6192

b)0.7422

c)0.8904

d)at least 151 sample is needed for 95% probability that sample mean falls within 8$ of the population mean.

Step-by-step explanation:

Let z(p) be the z-statistic of the probability that the mean price for a sample is within the margin of error. Then

z(p)= $\frac{ME*\sqrt{N}}{s }$ where

Me is the margin of error from the mean

s is the standard deviation of the population

N is the sample size

a.

z(p)= $\frac{8*\sqrt{30}}{50 }$ ≈ 0.8764

by looking z-table corresponding p value is 1-0.3808=0.6192

b.

z(p)= $\frac{8*\sqrt{50}}{50 }$ ≈ 1.1314

by looking z-table corresponding p value is 1-0.2578=0.7422

c.

z(p)= $\frac{8*\sqrt{100}}{50 }$ ≈ 1.6

by looking z-table corresponding p value is 1-0.1096=0.8904

d.

Minimum required sample size for 0.95 probability is

N≥ $(\frac{z*s}{ME} )^2$ where

N is the sample size

z is the corresponding z-score in 95% probability (1.96)

s is the standard deviation (50)

ME is the margin of error (8)

then N≥ $(\frac{1.96*50}{8} )^2$ ≈150.6

Thus at least 151 sample is needed for 95% probability that sample mean falls within 8$ of the population mean.

7 0

3 years ago

2(3x – 1) = –6x – 2 can someone help

Gnom [1K]

Let's solve your equation step-by-step.

2(3x−1)=−6x−2

Step 1: Simplify both sides of the equation.

2(3x−1)=−6x−2

(2)(3x)+(2)(−1)=−6x+−2(Distribute)

6x+−2=−6x+−2

6x−2=−6x−2

Step 2: Add 6x to both sides.

6x−2+6x=−6x−2+6x

12x−2=−2

Step 3: Add 2 to both sides.

12x−2+2=−2+2

12x=0

Step 4: Divide both sides by 12.

12x/12= 0/12

x=0

Answer:

x=0

HOPE THIS HELPS!!! :)

5 0

2 years ago

1.2.71

egoroff_w [7]

Answer:

Step-by-step explanation:

Set up an equation, where x is the number of gallons of 60% antifreeze solution.

Represent the percentages of antifreeze with decimal values.

0.6x + 0.3(80) = 0.5(x + 80)

Simplify and solve for x:

0.6x + 24 = 0.5x + 40

0.1x = 16

x = 160

So, you have to mix 160 gallons of a 60% antifreeze solution

6 0

2 years ago

Which expression is equivalent to (3x² + 3x - 3) - (6x² - 4x - 2)?

Marat540 [252]

Answer:

A. $12x^{4} -4x^{3} +3x^{2} +3x+20$

Step-by-step explanation:

For this problem, we have to combine like terms.

Let's look at the equation:

$(12x^{4} -4x^{3} +7x+6)+(3x^{2} -4x+14)$

$12x^{4$ , $-4x^{3}$ , $3x^{2}$ do not have any other like terms, so we keep all in the final answer.

$7x$ and $-4x$ are like terms, so we combine them. $7x-4x=3x$

14 and 6 are like terms, so we combine them. 14+6 = 20

Let's put everything into the final equation:

$12x^{4} -4x^{3} +3x^{2} +3x+20$

So, the final answer is A. $12x^{4} -4x^{3} +3x^{2} +3x+20$

Hope this helps! If you have any questions about my work, leave them in the comments below!

5 0

2 years ago

Simplify. 7x +84/(x + 12)(x+10)