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Finding the Fourth Proportional to 677.20, 1,015.90 and 330.55

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Solution

The fourth proportional to 677.20, 1,015.90 and 330.55 is: 495.87

Step by Step Solution

  1. Step 1: Write the proportion equation
    677.20 : 1,015.90 = 330.55 : x
  2. Step 2: Convert to fraction form
    677.20/1,015.90 = 330.55/x
  3. Step 3: Cross multiply
    677.20x = 1,015.90 × 330.55
  4. Step 4: Simplify right side
    677.20x = 335,805.75
  5. Step 5: Solve for x
    x = 335,805.75/677.20
  6. Step 6: Final answer
    x = 495.87

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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.