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Finding the Fourth Proportional to 339.54, 507.69 and 288.78

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Solution

The fourth proportional to 339.54, 507.69 and 288.78 is: 431.79

Step by Step Solution

  1. Step 1: Write the proportion equation
    339.54 : 507.69 = 288.78 : x
  2. Step 2: Convert to fraction form
    339.54/507.69 = 288.78/x
  3. Step 3: Cross multiply
    339.54x = 507.69 × 288.78
  4. Step 4: Simplify right side
    339.54x = 146,610.72
  5. Step 5: Solve for x
    x = 146,610.72/339.54
  6. Step 6: Final answer
    x = 431.79

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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.