All categories

3 years ago

3(x+3)=30 i have literally forgotten everything about algebra

Mathematics

1 answer:

zhannawk [14.2K]3 years ago

3 0

3(x+3)=30

3x+9=30

3x=21

x=7

You might be interested in

9 friends are sharing 12 pounds of peacans equally. how many pounds of peacans does each friend get?

lys-0071 [83]

1 pound evenly. ignore the remainder.

4 0

3 years ago

Fraction strip for 1/4, 2/8,3/12

Brilliant_brown [7]

4/16, 5/20, 6/24, 7/28, 8/32...

7 0

2 years ago

n automobile manufacturer claims that its van has a 37.4 miles/gallon (MPG) rating. An independent testing firm has been contrac

JulsSmile [24]

Answer:

Then z(s) is out of the acceptance region, we reject H₀, doubts of the independent testing firm are valids

Step-by-step explanation:

We will develop a Hypothesis Test ( a 2 tail test since the independent testing firm is interested in finding out if there is an incorrect MPG rating from the manufacturer

Test Hypothesis :

Null hypothesis H₀ μ = μ₀

Alternative Hypothesis Hₐ μ ≠ μ₀

Significance Level α = 0,05 α/2 = 0,025

z(c) for α/2 from z-table z(c) = - 1, 96 and by symmetry z(c) = 1,96

Calculating z(s)

z(s) = ( μ - μ₀ ) / σ /√n

z(s) = ( 37,8 - 37,4 ) / 2,3 /√280

z(s) = 0,4 * 16,73 / 2,3

z(s) = 2,90

Comparison between z(c) and z(s)

z(s) > z(c) 2,90 > 1,96

Then z(s) is out of the acceptance region, we reject H₀, doubts of the independent testing firm are valids

8 0

2 years ago

What is the coefficient and the constant in 4+x=15?

Dmitriy789 [7]

Problem: 4+x=15
- Subtract 4 from both sides
4+x-4=15-4
- Refine
x = 11

7 0

2 years ago

A researcher wishes to estimate, with 9090% confidence, the proportion of adults who have high-speed Internet access. Her es

Sunny_sXe [5.5K]

Answer: a) Required minimum sample size= 219

b) Required minimum sample size= 271

Step-by-step explanation:

As per given , we have

Margin of error : E= 5% =0.05

Critical z-value for 90% confidence interval : $z_{\alpha/2}=1.645$

a) Prior estimate of true proportion: p=28%=0.28

Formula to find the sample size :-

$n=p(1-p)(\dfrac{z_{\alpha/2}}{E})^2\\\\=0.28(1-0.28)(\dfrac{1.645}{0.05})^2\\\\=218.213856\approx219$

Required minimum sample size= 219

b) If no estimate of true proportion is given , then we assume p= 0.5

Formula to find the sample size :-

$n=0.5(1-0.5)(\dfrac{z_{\alpha/2}}{E})^2\\\\=0.25(\dfrac{1.645}{0.05})^2\\\\=270.6025\approx271$

Required minimum sample size= 271

8 0

2 years ago