When you want to change a cell color, which menu should you select?

A trucking firm has a large inventory of spare parts that have been in storage for a long time. It knowsthat some proportion of

Debora [2.8K]

Answer:

$0.1546\leq \widehat{p}\leq 0.3513$

Step-by-step explanation:

The firm tests 75 parts, and finds that 0.25 of them are notusable

n = 75

x = 0.25 \times 75 = 18.75≈19

$\widehat{p}=\frac{x}{n}$

$\widehat{p}=\frac{19}{75}$

$\widehat{p}=0.253$

Confidence level = 95%

So, Z_\alpha at 95% = 1.96

Formula of confidence interval of one sample proportion:

$=\widehat{p}-Z_\alpha \sqrt{\frac{\widehat{p}(1-\widehat{p}}{n}}\leq \widehat{p}\leq \widehat{p}+Z_\alpha \sqrt{\frac{\widehat{p}(1-\widehat{p}}{n}}$

$=0.253-(1.96)\sqrt{\frac{0.253(1-0.253)}{75}}\leq \widehat{p}\leq0.253+(1.96)\sqrt{\frac{0.253(1-0.253}{75}}$

Confidence interval $=0.1546\leq \widehat{p}\leq 0.3513$

7 0

4 years ago

Alana only has $56.47 saved for college, Brainstorm possible reasons why she has only managed to save this

LUCKY_DIMON [66]

Answer:

She could've spent more than she was making in a pay check

Step-by-step explanation:

4 0

4 years ago

Read 2 more answers

Which of these professionals most directly uses geometry?

notka56 [123]

Good Morning!
<span>air traffic controller
</span>

The most cited professional who uses geometry is the air traffic controller. This professional needs to calculate routes, distances and times traveled in order to avoid accumulation of aircraft at the time of landing, for example.

8 0

3 years ago

Tristen is building 3 trophies using Legos. He needs 324 total Legos. Tristen uses 220 Legos for the largest trophy and 135 Lego

Alexeev081 [22]

Answer: 166

Step-by-step explanation:

Number of trophies = 3

Total Legos required for all trophies = 324

Number of Legos for largest trophy(A) = 220

Number of Legos for smallest trophy(B) = 135

Number of Legos required for final trophy(C)

=?

Total Legos = [Number of Legos for largest trophy(A) + Number of Legos for smallest trophy(B) + Number of Legos required for final trophy(C)]

324 = 220 +135 + C

324 = 355 + C

324 - 355 = C

-31 = C

135 + 31 = 166

6 0

3 years ago

Read 2 more answers

What is the simplified form of x minus 2 over x squared plus x minus 6divided byx squared plus 5x plus 4 over x plus 4?

tatyana61 [14]

Answer:

$\dfrac{1}{x^2+4x+3}$

Step-by-step explanation:

You have asked for the simpilfied form of ...

$x-\dfrac{2}{x^2}+x-\dfrac{6}{x^2}+5x+\dfrac{4}{x}+4$

That would be ...

$\dfrac{7x^3+4x^2+4x-4}{x^2}$

We suspect that's not what you meant. Parentheses are required for grouping when you write math expressions in text form. They work best using math symbols instead of words. We think you mean

... ((x -2)/(x^2 +x -6))/((x^2 +5x +4)/(x +4))

_____

Maybe you want to simplify ...

$\displaystyle\frac{\left(\frac{x-2}{x^2+x-6}\right)}{\left(\frac{x^2+5x+4}{x+4}\right)}=\frac{(x-2)(x+4)}{(x-2)(x+3)(x+4)(x+1)}\\\\=\frac{1}{(x+1)(x+3)}=\frac{1}{x^2+4x+3}$

_____

<em>Comment on simplifying rational expressions</em>

Division of fractions works the same whether you're working with numbers or polynomials (or anything else). Dividing by something is the same as multiplying by its inverse (reciprocal).

(a/b)/(c/d) = (a/b)·(d/c)

I learned this as "invert and multiply". I've recently seen it referred to as "copy dot flip", meaning you copy the numerator, use a dot symbol to indicate multipication, then flip the denominator (make its reciprocal) to become what you're multiplying by.

8 0

3 years ago