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Finding the Fourth Proportional to 338.72, 508.28 and 143.78

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Solution

The fourth proportional to 338.72, 508.28 and 143.78 is: 215.75

Step by Step Solution

  1. Step 1: Write the proportion equation
    338.72 : 508.28 = 143.78 : x
  2. Step 2: Convert to fraction form
    338.72/508.28 = 143.78/x
  3. Step 3: Cross multiply
    338.72x = 508.28 × 143.78
  4. Step 4: Simplify right side
    338.72x = 73,077.24
  5. Step 5: Solve for x
    x = 73,077.24/338.72
  6. Step 6: Final answer
    x = 215.75

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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.