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Finding the Fourth Proportional to 420.03, 580.29 and 289.71

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Solution

The fourth proportional to 420.03, 580.29 and 289.71 is: 400.25

Step by Step Solution

  1. Step 1: Write the proportion equation
    420.03 : 580.29 = 289.71 : x
  2. Step 2: Convert to fraction form
    420.03/580.29 = 289.71/x
  3. Step 3: Cross multiply
    420.03x = 580.29 × 289.71
  4. Step 4: Simplify right side
    420.03x = 168,115.82
  5. Step 5: Solve for x
    x = 168,115.82/420.03
  6. Step 6: Final answer
    x = 400.25

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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.