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Finding the Fourth Proportional to 390.55, 539.06 and 224.78

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Solution

The fourth proportional to 390.55, 539.06 and 224.78 is: 310.25

Step by Step Solution

  1. Step 1: Write the proportion equation
    390.55 : 539.06 = 224.78 : x
  2. Step 2: Convert to fraction form
    390.55/539.06 = 224.78/x
  3. Step 3: Cross multiply
    390.55x = 539.06 × 224.78
  4. Step 4: Simplify right side
    390.55x = 121,169.91
  5. Step 5: Solve for x
    x = 121,169.91/390.55
  6. Step 6: Final answer
    x = 310.25

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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.