Answer : x = 20

Explanation :
3x + 2x +20 + 4x - 20 = 180

(3+2+4=9)

9x + 20 - 20
The 20s cancel each other out because one is positive and the other is negative

9x = 180

9x/9 = 180/9

X = 180 divided by 9

X = 20

7 0

3 years ago

An article gave the following summary information for fracture strengths (MPa) of n = 196 ceramic bars fired in a particular kil

Oliga [24]

Answer:

54.80 MPa to 55.92 MPa

Step-by-step explanation:

Sample mean fracture strength (x) = 55.36 MPa

Sample standard deviation (s) = 3.99 MPa

Sample size (n) = 196.

The upper and lower bounds for a 95% confidence interval are given by:

$U=x+1.960*\frac{s}{\sqrt{n}} \\L=x-1.960*\frac{s}{\sqrt{n}}$

The upper and lower bounds of the confidence interval are;

$U=55.36+1.960*\frac{3.99}{\sqrt{196}}\\U= 55.92\\L=55.36-1.960*\frac{3.99}{\sqrt{196}}\\L= 54.80\\$

The 95% confidence interval for true average fracture strength is 54.80 MPa to 55.92 MPa

4 0

4 years ago

What is UT?<br> UV= 8<br> TV= 17<br><br> UT= ?

DerKrebs [107]

The correct answer is 15.

3 0

3 years ago