Water and wastewater · Worked step by step
What is the area of a 50 by 20 foot basin?
If math has never been your thing, you are in the right place. Try it on paper first, then we write it out with you, one small step at a time, and explain every step in plain words so you never lose the thread.
The problem
A rectangular basin is 50 feet long and 20 feet wide. What is its area?
Grab a pen and paper first
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Watch it solved, with you
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Press play and I’ll write it out with you, one small step at a time.
Every step gets a plain-words explanation here, so you always know exactly what just happened and why.
The written version, step by step
- 1
Write the two sides
length = 50 ft • width = 20 ft
- A rectangle just needs its two sides.
- Length 50, width 20.
- Both in feet, nothing to convert.
- 2
Multiply length by width
area = 50 × 20 • area = 1,000 sq ft
- Area is length times width.
- 50 × 20 = 1,000.
- So the area is 1,000 square feet.
Quick trick: 50 × 20: multiply 5 × 2 = 10, then add the two zeros back, giving 1,000.
Remember this for good
Rectangle area is length times width, in square feet.
50 rows of 20 tiles, or 20 rows of 50; either way, 50 times 20 tiles of 1 foot each is 1,000 square feet.
Solve it fast next time
- Rectangle area = length times width.
- Answer is in square feet.
- It is the first step of the basin's volume and loading.
The answer: 1,000 square feet.