Answer:
Width of pool is 25 feet
Explanation:
Let the width be x
Now we are given that length is three times as long as it is wide.
Length = 3x
Now we are given that it has a border around it that measures 200 feet total.
Perimeter of Swimming pool =
![2(Length +Breadth)](https://img.qammunity.org/2020/formulas/mathematics/high-school/y63tyddys4msaea2r2x0cvt9dw20l22taa.png)
Perimeter of Swimming pool =
![2(3x +x)](https://img.qammunity.org/2020/formulas/mathematics/high-school/m505vr4bwttcd9wdm783gkp5wex2p6igt9.png)
Perimeter of Swimming pool =
![8x](https://img.qammunity.org/2020/formulas/mathematics/middle-school/dl1tsvp6ozj0p1pvqkwub4x3g00qidl21k.png)
So, ATQ
![8x=200](https://img.qammunity.org/2020/formulas/mathematics/high-school/hrd47mtiavzbwd4j6e3x3239aeporhg13t.png)
![x=(200)/(8)](https://img.qammunity.org/2020/formulas/mathematics/high-school/gzkvks4winqp83gwwbcyjrgihfv2n7nvjs.png)
![x=25](https://img.qammunity.org/2020/formulas/mathematics/high-school/u4xxcasp014x5afmoh88owxfnty4jr97c6.png)
Hence Width of swimming pool is 25 feet