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Finding the Fourth Proportional to 420.53, 580.13 and 280.51

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Solution

The fourth proportional to 420.53, 580.13 and 280.51 is: 386.97

Step by Step Solution

  1. Step 1: Write the proportion equation
    420.53 : 580.13 = 280.51 : x
  2. Step 2: Convert to fraction form
    420.53/580.13 = 280.51/x
  3. Step 3: Cross multiply
    420.53x = 580.13 × 280.51
  4. Step 4: Simplify right side
    420.53x = 162,731.52
  5. Step 5: Solve for x
    x = 162,731.52/420.53
  6. Step 6: Final answer
    x = 386.97

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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.