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Finding the Fourth Proportional to 519.90, 780.66 and 276.90

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Solution

The fourth proportional to 519.90, 780.66 and 276.90 is: 415.78

Step by Step Solution

  1. Step 1: Write the proportion equation
    519.90 : 780.66 = 276.90 : x
  2. Step 2: Convert to fraction form
    519.90/780.66 = 276.90/x
  3. Step 3: Cross multiply
    519.90x = 780.66 × 276.90
  4. Step 4: Simplify right side
    519.90x = 216,164.75
  5. Step 5: Solve for x
    x = 216,164.75/519.90
  6. Step 6: Final answer
    x = 415.78

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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.