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Word problemsArithmeticMiddle schoolabout 0:44

Find the circumference of a circle with radius 5: animated lesson

A narrated, step-by-step word problems video lesson with captions. Final answer: Circumference = 10π ≈ 31.41592654.

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Video with a synthetic English voice and captions. Pick another language for subtitles in that language, or open the interactive version.

Video narrated by a synthetic voice (Piper TTS, en_US-ljspeech-high voice (LJ Speech dataset, public domain)); the steps come from our maths engine and the answer was checked independently. Download MP4 (0.3 MB) · Captions (WebVTT)

Steps on screen

1. The problem
Worked example
Find the circumference of a circle with radius 5
2. Step by step
1. Read the problem
2. Circumference
3. The answer
$\text{Circumference = 10π ≈ 31.41592654}$
Circumference = 10π ≈ 31.41592654
4. Check
- C / (2π) = 5 ✓

Transcript

The problem. Here is the problem: Find the circumference of a circle with radius 5. Circle with radius 5; circumference C equals 2pir.

Step by step. Read the problem. Radius r equals 5. Circumference. C equals 2pir equals 2pi times 5 equals 10pi approximately 31.41592654.

The answer. So the answer is Circumference equals 10pi approximately 31.41592654. Circle with radius 5; circumference C equals 2pir.

Check. C / (2pi) equals 5, which checks out.

About word problems

Turn everyday situations about prices, speed, ages and interest into equations and solve them.

Find the circumference of a circle with radius 5 (Lesson)