Assignment

Mathematics

1 answer:

kvv77 [185]3 years ago

6 0

Answer:

step by step equation:

Lindsay owns 12 books.

Step-by-step explanation:

We can solve this question using a system of equations.

I am going to say that:

x is the number of books that Lindsay owns.

y is the nuber of books that Destiny owns.

z is the number of books that Henry owns.

Lindsay owns one-third the number of books that Destiny owns.

This means that:

, or

Henry owns a fourth as many books as Destiny.

This means that , or . Also, in function of x, we may have

Together they own 57 books.

This means that

We want to find x. So

Lindsay owns 12 books.

You might be interested in

Is The polar form of a complex number is unique?

Pie

Answer:

Step-by-step explanation:

The angle in the polar form of a complex number can have any multiple of 2π radians added to it, and the number will be the same number. That is, there are an infinite number of representations of a complex number in polar form.

6 0

3 years ago

A survey of 85 families showed that 36 owned at least one DVD player. Find the 99% confidence interval estimate of the true prop

attashe74 [19]

Answer:

$0.424 - 2.58\sqrt{\frac{0.424(1-0.424)}{85}}=0.286$

$0.424 + 2.58\sqrt{\frac{0.424(1-0.424)}{85}}=0.562$

The 99% confidence interval would be given by (0.286;0.562)

Step-by-step explanation:

Information given:

$X= 36$ represent the families owned at least one DVD player

$n= 85$ represent the total number of families

$\hat p=\frac{36}{85}= 0.424$ represent the estimated proportion of families owned at least one DVD player

In order to find the critical value we need to take in count that we are finding the interval for a proportion, so on this case we need to use the z distribution. Since our interval is at 99% of confidence, our significance level would be given by $\alpha=1-0.99=0.01$ and $\alpha/2 =0.05$ . And the critical value would be given by: