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Finding the Fourth Proportional to 505.91, 698.11 and 309.39

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Solution

The fourth proportional to 505.91, 698.11 and 309.39 is: 426.93

Step by Step Solution

  1. Step 1: Write the proportion equation
    505.91 : 698.11 = 309.39 : x
  2. Step 2: Convert to fraction form
    505.91/698.11 = 309.39/x
  3. Step 3: Cross multiply
    505.91x = 698.11 × 309.39
  4. Step 4: Simplify right side
    505.91x = 215,988.25
  5. Step 5: Solve for x
    x = 215,988.25/505.91
  6. Step 6: Final answer
    x = 426.93

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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.