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Finding the Fourth Proportional to 490.60, 675.87 and 420.43

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Solution

The fourth proportional to 490.60, 675.87 and 420.43 is: 579.20

Step by Step Solution

  1. Step 1: Write the proportion equation
    490.60 : 675.87 = 420.43 : x
  2. Step 2: Convert to fraction form
    490.60/675.87 = 420.43/x
  3. Step 3: Cross multiply
    490.60x = 675.87 × 420.43
  4. Step 4: Simplify right side
    490.60x = 284,156.02
  5. Step 5: Solve for x
    x = 284,156.02/490.60
  6. Step 6: Final answer
    x = 579.20

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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.