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Finding the Fourth Proportional to 338.79, 508.19 and 261.87

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Solution

The fourth proportional to 338.79, 508.19 and 261.87 is: 392.81

Step by Step Solution

  1. Step 1: Write the proportion equation
    338.79 : 508.19 = 261.87 : x
  2. Step 2: Convert to fraction form
    338.79/508.19 = 261.87/x
  3. Step 3: Cross multiply
    338.79x = 508.19 × 261.87
  4. Step 4: Simplify right side
    338.79x = 133,079.72
  5. Step 5: Solve for x
    x = 133,079.72/338.79
  6. Step 6: Final answer
    x = 392.81

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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.