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Finding the Fourth Proportional to 420.27, 580.15 and 278.56

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Solution

The fourth proportional to 420.27, 580.15 and 278.56 is: 384.53

Step by Step Solution

  1. Step 1: Write the proportion equation
    420.27 : 580.15 = 278.56 : x
  2. Step 2: Convert to fraction form
    420.27/580.15 = 278.56/x
  3. Step 3: Cross multiply
    420.27x = 580.15 × 278.56
  4. Step 4: Simplify right side
    420.27x = 161,606.58
  5. Step 5: Solve for x
    x = 161,606.58/420.27
  6. Step 6: Final answer
    x = 384.53

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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.