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Finding the Fourth Proportional to 420.29, 580.09 and 254.47

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Solution

The fourth proportional to 420.29, 580.09 and 254.47 is: 351.22

Step by Step Solution

  1. Step 1: Write the proportion equation
    420.29 : 580.09 = 254.47 : x
  2. Step 2: Convert to fraction form
    420.29/580.09 = 254.47/x
  3. Step 3: Cross multiply
    420.29x = 580.09 × 254.47
  4. Step 4: Simplify right side
    420.29x = 147,612.63
  5. Step 5: Solve for x
    x = 147,612.63/420.29
  6. Step 6: Final answer
    x = 351.22

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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.