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Finding the Fourth Proportional to 505.85, 698.08 and 309.35

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Solution

The fourth proportional to 505.85, 698.08 and 309.35 is: 426.91

Step by Step Solution

  1. Step 1: Write the proportion equation
    505.85 : 698.08 = 309.35 : x
  2. Step 2: Convert to fraction form
    505.85/698.08 = 309.35/x
  3. Step 3: Cross multiply
    505.85x = 698.08 × 309.35
  4. Step 4: Simplify right side
    505.85x = 215,951.05
  5. Step 5: Solve for x
    x = 215,951.05/505.85
  6. Step 6: Final answer
    x = 426.91

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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.