Question

Suppose you want to place a shelf that is 30 1/3 inches long in the center of a wall that is 45 3/4 inches wide. About how fare from each edge of the wall should tou place the shelf?

Answer 1

7.71 inches far from each edge of the wall you should place the shelf.

Explanation:

Given:

`\textrm{size of a shelf}=30(1)/(3) =(91)/(3)=30.33\ inches\\\textrm{size of a wall}=45(3)/(4) =(183)/(4)=45.75\ inches\\`

Let,

AB = distance between the edges or distance of wall.

ED = size of the shelf.

C is the centre of the wall.

To Find:

Distance from the edge of the wall to the shelf, when the shell is placed at the center of the wall.

AE = DB = ?

Solution:

As we need to place the shelf exactly in the center.

First we will calculate the distance from the center of the wall to the edge.

So the distance from the centre of the wall to the edge will be exactly half of the size of the wall.

`CB = (1)/(2)* AB\\ =(1)/(2)* 45.75\\\therefore CB=22.875\ inches`

now the distance from the centre to the end of the shelf will be exactly half of the size of the shelf.

`CE = (1)/(2)* DE\\ =(1)/(2)* 30.33\\\therefore CB=15.165\ inches`

Now we want to calculate the distance from the edge of the wall to the shelf,that is the distance from the end of the shelf to the edge of the wall.

`AE=BD= BC-CD\\=22.875-15.165\\=7.71\ inches\\\therefore AE = BD = 7.71\ inches`

Therefore, 7.71 inches far from each edge of the wall you should place the shelf.