Question

Writing an equation help need?

The hardcover books produced by a publisher have pages that are 0.1 millimeter thick and a front cover and a back cover that each are 2 millimeters thick. Which of the following gives the total thickness f of n, in millimeters, of a closed book that has n pages?

Answer 1

Well... a page is `0.1" millimetre"` So... if there are `n` pages......

The total thickness of the pages are `0.1n" millimetres"`

The front and the back cover are `2" millimetres thick each"` so
that adds `4" millimetres more"`

So in the end.. the book has a total thickness of:

`0.1n+4" millimetres"`

`n/10+4" millimetres"`

Answer 2

The equation would be`:`

`f(n)=0.1(n)+4`

Explanation:

Te question asks for the total thickness of a closed book so adding the 2 millimeters for each front cover and the back cover.

`n` is the number of pages and each page is `0.1` millimeters thick sop you would multiply `0.1` by `n` to find out the thickness of the book for `n` number of pages. Then add the front cover and the back cover which is `2` millimeters each. Both the back and the front would be `4` millimeters all together so in the equation instead of adding `2+2` you would add 4.

So `f` of `n=`

`0.1(n)+4`