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Finding the Fourth Proportional to 339.30, 508.30 and 261.30

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Solution

The fourth proportional to 339.30, 508.30 and 261.30 is: 391.45

Step by Step Solution

  1. Step 1: Write the proportion equation
    339.30 : 508.30 = 261.30 : x
  2. Step 2: Convert to fraction form
    339.30/508.30 = 261.30/x
  3. Step 3: Cross multiply
    339.30x = 508.30 × 261.30
  4. Step 4: Simplify right side
    339.30x = 132,818.79
  5. Step 5: Solve for x
    x = 132,818.79/339.30
  6. Step 6: Final answer
    x = 391.45

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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.