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Finding the Fourth Proportional to 505.86, 698.28 and 394.90

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Solution

The fourth proportional to 505.86, 698.28 and 394.90 is: 545.11

Step by Step Solution

  1. Step 1: Write the proportion equation
    505.86 : 698.28 = 394.90 : x
  2. Step 2: Convert to fraction form
    505.86/698.28 = 394.90/x
  3. Step 3: Cross multiply
    505.86x = 698.28 × 394.90
  4. Step 4: Simplify right side
    505.86x = 275,750.77
  5. Step 5: Solve for x
    x = 275,750.77/505.86
  6. Step 6: Final answer
    x = 545.11

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.