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Finding the Fourth Proportional to 420.38, 579.76 and 254.56

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Solution

The fourth proportional to 420.38, 579.76 and 254.56 is: 351.07

Step by Step Solution

  1. Step 1: Write the proportion equation
    420.38 : 579.76 = 254.56 : x
  2. Step 2: Convert to fraction form
    420.38/579.76 = 254.56/x
  3. Step 3: Cross multiply
    420.38x = 579.76 × 254.56
  4. Step 4: Simplify right side
    420.38x = 147,583.71
  5. Step 5: Solve for x
    x = 147,583.71/420.38
  6. Step 6: Final answer
    x = 351.07

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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.