Home / 12,911.20-19,366.80-7,986.40

Finding the Fourth Proportional to 12,911.20, 19,366.80 and 7,986.40

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Solution

The fourth proportional to 12,911.20, 19,366.80 and 7,986.40 is: 11,979.60

Step by Step Solution

  1. Step 1: Write the proportion equation
    12,911.20 : 19,366.80 = 7,986.40 : x
  2. Step 2: Convert to fraction form
    12,911.20/19,366.80 = 7,986.40/x
  3. Step 3: Cross multiply
    12,911.20x = 19,366.80 × 7,986.40
  4. Step 4: Simplify right side
    12,911.20x = 154,671,011.52
  5. Step 5: Solve for x
    x = 154,671,011.52/12,911.20
  6. Step 6: Final answer
    x = 11,979.60

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Similar ratio
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1.5x scale

Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.