Skip to content
MathSolver Pro
  • Open the math solver
  • Ask the AI tutor
  • Find an AP course
  • Create a quiz
  • Open the calculator
  • Graphing Calculator
  • Browse all calculators
  • Read math guides
↑ ↓Enter to open · Esc to close
Solve a problem
Order of operationsArithmeticElementary schoolabout 1:06

Evaluate 6 + 12 * (4 - 9) / 7: animated lesson

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

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 (0.4 MB) · Captions (WebVTT)

Steps on screen

  1. 1. The problem
    Worked example
    6 + 12 * (4 - 9) / 7
  2. 2. Steps, part 1
    1. 4−9=−54 - 9 = -5
      Subtract the whole numbers
    2. 12×(−5)=12×(−5)1×1=−6012 \times \left(-5\right) = \frac{12 \times (-5)}{1 \times 1} = -60
      Multiply numerators and multiply denominators
    3. −60÷7=−60×17-60 \div 7 = -60 \times \frac{1}{7}
      Dividing by a fraction means multiplying by its reciprocal
    4. −60×17=−60×11×7=−607-60 \times \frac{1}{7} = \frac{-60 \times 1}{1 \times 7} = -\frac{60}{7}
      Multiply numerators and multiply denominators
  3. 3. Steps, part 2
    1. 6+(−607)=427+(−607)6 + \left(-\frac{60}{7}\right) = \frac{42}{7} + \left(-\frac{60}{7}\right)
      Rewrite both fractions with the least common denominator
    2. 42+(−60)7=−187\frac{42 + (-60)}{7} = -\frac{18}{7}
      Add the numerators and keep the denominator
    3. −187=−247-\frac{18}{7} = -2\tfrac{4}{7}
      Final answer in lowest terms
  4. 4. The answer
    −187-\frac{18}{7}

    6 + 12 * (4 - 9) / 7 = -18/7

  5. 5. Check
    • Decimal check: -18/7 ≈ -2.571428571
    • As a mixed number: -2 4/7

Transcript

The problem. Here is the problem: 6 plus 12 times (4 minus 9) / 7. Exact arithmetic with fractions (results kept in lowest terms).

Steps, part 1. Subtract the whole numbers. Multiply numerators and multiply denominators. Dividing by a fraction means multiplying by its reciprocal. Multiply numerators and multiply denominators.

Steps, part 2. Rewrite both fractions with the least common denominator. The LCD of 1 and 7 is 7. Add the numerators and keep the denominator. Final answer in lowest terms.

The answer. So the answer is negative 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: negative 18 over 7 approximately negative 2.571428571. As a mixed number: negative 2 4 over 7.

About order of operations

Evaluate expressions with brackets, powers, multiplication, division, addition and subtraction in the right order.

More lessons like this

Evaluate 6 + 12 * (4 - 9) / 7: Animated Step-by-Step Lesson