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Finding the Fourth Proportional to 420.29, 580.03 and 243.31

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Solution

The fourth proportional to 420.29, 580.03 and 243.31 is: 335.78

Step by Step Solution

  1. Step 1: Write the proportion equation
    420.29 : 580.03 = 243.31 : x
  2. Step 2: Convert to fraction form
    420.29/580.03 = 243.31/x
  3. Step 3: Cross multiply
    420.29x = 580.03 × 243.31
  4. Step 4: Simplify right side
    420.29x = 141,125.95
  5. Step 5: Solve for x
    x = 141,125.95/420.29
  6. Step 6: Final answer
    x = 335.78

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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.