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Finding the Fourth Proportional to 520.20, 778.95 and 412.20

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Solution

The fourth proportional to 520.20, 778.95 and 412.20 is: 617.23

Step by Step Solution

  1. Step 1: Write the proportion equation
    520.20 : 778.95 = 412.20 : x
  2. Step 2: Convert to fraction form
    520.20/778.95 = 412.20/x
  3. Step 3: Cross multiply
    520.20x = 778.95 × 412.20
  4. Step 4: Simplify right side
    520.20x = 321,083.19
  5. Step 5: Solve for x
    x = 321,083.19/520.20
  6. Step 6: Final answer
    x = 617.23

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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.