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Finding the Fourth Proportional to 420.60, 580.49 and 254.91

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Solution

The fourth proportional to 420.60, 580.49 and 254.91 is: 351.81

Step by Step Solution

  1. Step 1: Write the proportion equation
    420.60 : 580.49 = 254.91 : x
  2. Step 2: Convert to fraction form
    420.60/580.49 = 254.91/x
  3. Step 3: Cross multiply
    420.60x = 580.49 × 254.91
  4. Step 4: Simplify right side
    420.60x = 147,971.43
  5. Step 5: Solve for x
    x = 147,971.43/420.60
  6. Step 6: Final answer
    x = 351.81

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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.