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Finding the Fourth Proportional to 420.49, 580.76 and 280.37

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Solution

The fourth proportional to 420.49, 580.76 and 280.37 is: 387.23

Step by Step Solution

  1. Step 1: Write the proportion equation
    420.49 : 580.76 = 280.37 : x
  2. Step 2: Convert to fraction form
    420.49/580.76 = 280.37/x
  3. Step 3: Cross multiply
    420.49x = 580.76 × 280.37
  4. Step 4: Simplify right side
    420.49x = 162,827.68
  5. Step 5: Solve for x
    x = 162,827.68/420.49
  6. Step 6: Final answer
    x = 387.23

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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.