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Finding the Fourth Proportional to 420.61, 580.44 and 254.79

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Solution

The fourth proportional to 420.61, 580.44 and 254.79 is: 351.61

Step by Step Solution

  1. Step 1: Write the proportion equation
    420.61 : 580.44 = 254.79 : x
  2. Step 2: Convert to fraction form
    420.61/580.44 = 254.79/x
  3. Step 3: Cross multiply
    420.61x = 580.44 × 254.79
  4. Step 4: Simplify right side
    420.61x = 147,890.31
  5. Step 5: Solve for x
    x = 147,890.31/420.61
  6. Step 6: Final answer
    x = 351.61

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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.