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Finding the Fourth Proportional to 412.78, 619.10 and 207.30

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Solution

The fourth proportional to 412.78, 619.10 and 207.30 is: 310.91

Step by Step Solution

  1. Step 1: Write the proportion equation
    412.78 : 619.10 = 207.30 : x
  2. Step 2: Convert to fraction form
    412.78/619.10 = 207.30/x
  3. Step 3: Cross multiply
    412.78x = 619.10 × 207.30
  4. Step 4: Simplify right side
    412.78x = 128,339.43
  5. Step 5: Solve for x
    x = 128,339.43/412.78
  6. Step 6: Final answer
    x = 310.91

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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.