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Finding the Fourth Proportional to 519.80, 780.38 and 365.80

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Solution

The fourth proportional to 519.80, 780.38 and 365.80 is: 549.18

Step by Step Solution

  1. Step 1: Write the proportion equation
    519.80 : 780.38 = 365.80 : x
  2. Step 2: Convert to fraction form
    519.80/780.38 = 365.80/x
  3. Step 3: Cross multiply
    519.80x = 780.38 × 365.80
  4. Step 4: Simplify right side
    519.80x = 285,464.12
  5. Step 5: Solve for x
    x = 285,464.12/519.80
  6. Step 6: Final answer
    x = 549.18

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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.