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Finding the Fourth Proportional to 390.70, 539.21 and 224.92

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Solution

The fourth proportional to 390.70, 539.21 and 224.92 is: 310.41

Step by Step Solution

  1. Step 1: Write the proportion equation
    390.70 : 539.21 = 224.92 : x
  2. Step 2: Convert to fraction form
    390.70/539.21 = 224.92/x
  3. Step 3: Cross multiply
    390.70x = 539.21 × 224.92
  4. Step 4: Simplify right side
    390.70x = 121,279.11
  5. Step 5: Solve for x
    x = 121,279.11/390.70
  6. Step 6: Final answer
    x = 310.41

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.