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FractionsArithmeticElementary schoolabout 0:47

Calculate 9/7 / 2/4: animated lesson

A narrated, step-by-step fractions video lesson with captions. Final answer: 18/7.

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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
9/7 / 2/4
2. Step by step
1. $\frac{9}{7} \div \frac{1}{2} = \frac{9}{7} \times 2$
  Dividing by a fraction means multiplying by its reciprocal
2. $\frac{9}{7} \times 2 = \frac{9 \times 2}{7 \times 1} = \frac{18}{7}$
  Multiply numerators and multiply denominators
3. $\frac{18}{7} = 2\tfrac{4}{7}$
  Final answer in lowest terms
3. The answer
$\frac{18}{7}$
9/7 / 2/4 = 18/7
4. Check
- Decimal check: 18/7 ≈ 2.571428571
- As a mixed number: 2 4/7

Transcript

The problem. Here is the problem: 9 over 7 / 2 over 4. Exact arithmetic with fractions (results kept in lowest terms).

Step by step. Dividing by a fraction means multiplying by its reciprocal. Multiply numerators and multiply denominators. Final answer in lowest terms.

The answer. So the answer is 18 over 7. Fractions are combined over a common denominator for addition and subtraction, multiplied straight across, and divided by multiplying by the reciprocal. The result is reduced by the greatest common factor.

Check. Decimal check: 18 over 7 approximately 2.571428571. As a mixed number: 2 4 over 7.

About fractions

Add, subtract, multiply and divide fractions, finding common denominators and simplifying the result.

Calculate 9/7 / 2/4: Fractions Step-by-Step Lesson