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Finding the Fourth Proportional to 420.35, 580.25 and 376.61

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Solution

The fourth proportional to 420.35, 580.25 and 376.61 is: 519.87

Step by Step Solution

  1. Step 1: Write the proportion equation
    420.35 : 580.25 = 376.61 : x
  2. Step 2: Convert to fraction form
    420.35/580.25 = 376.61/x
  3. Step 3: Cross multiply
    420.35x = 580.25 × 376.61
  4. Step 4: Simplify right side
    420.35x = 218,526.07
  5. Step 5: Solve for x
    x = 218,526.07/420.35
  6. Step 6: Final answer
    x = 519.87

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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.