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Finding the Fourth Proportional to 490.38, 734.82 and 420.58

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Solution

The fourth proportional to 490.38, 734.82 and 420.58 is: 630.23

Step by Step Solution

  1. Step 1: Write the proportion equation
    490.38 : 734.82 = 420.58 : x
  2. Step 2: Convert to fraction form
    490.38/734.82 = 420.58/x
  3. Step 3: Cross multiply
    490.38x = 734.82 × 420.58
  4. Step 4: Simplify right side
    490.38x = 309,050.60
  5. Step 5: Solve for x
    x = 309,050.60/490.38
  6. Step 6: Final answer
    x = 630.23

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.