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Finding the Fourth Proportional to 338.38, 508.18 and 257.80

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Solution

The fourth proportional to 338.38, 508.18 and 257.80 is: 387.16

Step by Step Solution

  1. Step 1: Write the proportion equation
    338.38 : 508.18 = 257.80 : x
  2. Step 2: Convert to fraction form
    338.38/508.18 = 257.80/x
  3. Step 3: Cross multiply
    338.38x = 508.18 × 257.80
  4. Step 4: Simplify right side
    338.38x = 131,008.80
  5. Step 5: Solve for x
    x = 131,008.80/338.38
  6. Step 6: Final answer
    x = 387.16

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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.