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Finding the Fourth Proportional to 559.80, 839.70 and 519.30

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Solution

The fourth proportional to 559.80, 839.70 and 519.30 is: 778.95

Step by Step Solution

  1. Step 1: Write the proportion equation
    559.80 : 839.70 = 519.30 : x
  2. Step 2: Convert to fraction form
    559.80/839.70 = 519.30/x
  3. Step 3: Cross multiply
    559.80x = 839.70 × 519.30
  4. Step 4: Simplify right side
    559.80x = 436,056.21
  5. Step 5: Solve for x
    x = 436,056.21/559.80
  6. Step 6: Final answer
    x = 778.95

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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.