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FractionsArithmeticElementary schoolabout 0:44

Calculate 9/3 + 4/8: animated lesson

A narrated, step-by-step fractions video lesson with captions. Final answer: 7/2.

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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
9/3 + 4/8
2. Step by step
1. $3 + \frac{1}{2} = \frac{6}{2} + \frac{1}{2}$
  Rewrite both fractions with the least common denominator
2. $\frac{6 + 1}{2} = \frac{7}{2}$
  Add the numerators and keep the denominator
3. $\frac{7}{2} = 3\tfrac{1}{2}$
  Final answer in lowest terms
3. The answer
$\frac{7}{2}$
9/3 + 4/8 = 7/2
4. Check
- Decimal check: 7/2 ≈ 3.5
- As a mixed number: 3 1/2

Transcript

The problem. Here is the problem: 9 over 3 plus 4 over 8. Exact arithmetic with fractions (results kept in lowest terms).

Step by step. Rewrite both fractions with the least common denominator. The LCD of 1 and 2 is 2. Add the numerators and keep the denominator. Final answer in lowest terms.

The answer. So the answer is 7 over 2. 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: 7 over 2 approximately 3.5. As a mixed number: 3 1 over 2.

About fractions

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

Calculate 9/3 + 4/8: Fractions Step-by-Step Lesson