Home / 1,287.20-1,929.18-556.40

Finding the Fourth Proportional to 1,287.20, 1,929.18 and 556.40

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Solution

The fourth proportional to 1,287.20, 1,929.18 and 556.40 is: 833.90

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,287.20 : 1,929.18 = 556.40 : x
  2. Step 2: Convert to fraction form
    1,287.20/1,929.18 = 556.40/x
  3. Step 3: Cross multiply
    1,287.20x = 1,929.18 × 556.40
  4. Step 4: Simplify right side
    1,287.20x = 1,073,395.75
  5. Step 5: Solve for x
    x = 1,073,395.75/1,287.20
  6. Step 6: Final answer
    x = 833.90

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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.