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Finding the Fourth Proportional to 612.20, 920.12 and 539.30

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Solution

The fourth proportional to 612.20, 920.12 and 539.30 is: 810.55

Step by Step Solution

  1. Step 1: Write the proportion equation
    612.20 : 920.12 = 539.30 : x
  2. Step 2: Convert to fraction form
    612.20/920.12 = 539.30/x
  3. Step 3: Cross multiply
    612.20x = 920.12 × 539.30
  4. Step 4: Simplify right side
    612.20x = 496,220.72
  5. Step 5: Solve for x
    x = 496,220.72/612.20
  6. Step 6: Final answer
    x = 810.55

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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.