Question

The rectangular projection screen in the school auditorium is 5 times as long and 5 times as wide as the rectangular screen in the library. The screen in the library is 4 feet long with a perimeter of 14 feet. What is the perimeter of the screen in the auditorium

Answer 1

Library: length 4, width 3 = 4(2)+3(2)=14

Take the length and width and multiply them by 5.

4*5=20 and 3*5=15

20(2)+15(2)= 70

The perimeter of the auditorium screen is 70.

Answer 2

The perimeter of the screen in the auditorium is 70 feet .

Explanation:

Length of screen in library = 4 feet

Perimeter of screen in library = 2(l+b)=2(4+b)

We are given that the Perimeter of screen in library is 14 feet

So,
`2(4+b)=14`

`4+b=7`

`b=3`

Width of screen in library = 3 feet

The rectangular projection screen in the school auditorium is 5 times as long as the rectangular screen in the library.

So, Length of screen in auditorium =
`5 * 4 = 20 feet`

The rectangular projection screen in the school auditorium is 5 times as wide as the rectangular screen in the library.

So, Width of screen in auditorium =
`5 * 3 = 15 feet`

Perimeter of the screen in the auditorium = 2(l+b)=2(20+15)= 70

Hence the perimeter of the screen in the auditorium is 70 feet .