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Finding the Fourth Proportional to 391.45, 586.67 and 339.20

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Solution

The fourth proportional to 391.45, 586.67 and 339.20 is: 508.37

Step by Step Solution

  1. Step 1: Write the proportion equation
    391.45 : 586.67 = 339.20 : x
  2. Step 2: Convert to fraction form
    391.45/586.67 = 339.20/x
  3. Step 3: Cross multiply
    391.45x = 586.67 × 339.20
  4. Step 4: Simplify right side
    391.45x = 198,998.23
  5. Step 5: Solve for x
    x = 198,998.23/391.45
  6. Step 6: Final answer
    x = 508.37

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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.