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Finding the Fourth Proportional to 619.31, 929.13 and 208.49

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Solution

The fourth proportional to 619.31, 929.13 and 208.49 is: 312.79

Step by Step Solution

  1. Step 1: Write the proportion equation
    619.31 : 929.13 = 208.49 : x
  2. Step 2: Convert to fraction form
    619.31/929.13 = 208.49/x
  3. Step 3: Cross multiply
    619.31x = 929.13 × 208.49
  4. Step 4: Simplify right side
    619.31x = 193,714.31
  5. Step 5: Solve for x
    x = 193,714.31/619.31
  6. Step 6: Final answer
    x = 312.79

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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.