Answer:
There are 271.74 ft^2 not covered by the rug
The percentage not covered by the rug is 90.58%
Explanation:
step 1
Find out the area of the room
The area of the rectangular room is
![A=(15)(20)=300\ ft^2](https://img.qammunity.org/2020/formulas/mathematics/middle-school/jv86s55gmz3mlwjskbbmy6uysh1ndnw7ru.png)
step 2
Find out the area of the circular rug
The area of the circle is
![A=\pi r^(2)](https://img.qammunity.org/2020/formulas/mathematics/middle-school/2z11w6ajg8k9itft7shcdqinea4lmf008k.png)
we have
![\pi =3.14](https://img.qammunity.org/2020/formulas/mathematics/high-school/595myhvi9x0vjp0b1ku7bsoelmk1x8jihg.png)
----> the radius is half the diameter
substitute
![A=(3.14)(3)^(2)](https://img.qammunity.org/2020/formulas/mathematics/middle-school/5gfqf5am4k3f92dgq23c792g2ikj3l5vca.png)
![A=28.26\ ft^(2)](https://img.qammunity.org/2020/formulas/mathematics/middle-school/xbso0js5jz9wtxkp8i734ra2r73973p2kd.png)
step 3
Find out what percentage of the room is not covered by the rug
we know that
300 ft^2 represent the 100%
so
using proportion
Find out what percentage represent the difference (300-28.26)=271.74 ft^2
Let
x ----> the percentage not covered by the rug
![(300)/(100\%)=(271.74)/(x)\\\\x=100(271.74)/300\\\\x=90.58\%](https://img.qammunity.org/2020/formulas/mathematics/middle-school/3ayhkrcpmeurrqthakeq3v6pvk6aj7oi7t.png)
Convert to fraction form
![90.58\%=(90.58)/(100)](https://img.qammunity.org/2020/formulas/mathematics/middle-school/1m6t0ei6mr827i7314b7jnracju20bycqp.png)
Simplify
![(4,529)/(5,000)](https://img.qammunity.org/2020/formulas/mathematics/middle-school/4pnaxwyozeec04fs4yfffa35mh1vw4hpo5.png)
therefore
There are 271.74 ft^2 not covered by the rug
The percentage not covered by the rug is 90.58%