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Finding the Fourth Proportional to 490.02, 671.55 and 489.20

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Solution

The fourth proportional to 490.02, 671.55 and 489.20 is: 670.43

Step by Step Solution

  1. Step 1: Write the proportion equation
    490.02 : 671.55 = 489.20 : x
  2. Step 2: Convert to fraction form
    490.02/671.55 = 489.20/x
  3. Step 3: Cross multiply
    490.02x = 671.55 × 489.20
  4. Step 4: Simplify right side
    490.02x = 328,522.26
  5. Step 5: Solve for x
    x = 328,522.26/490.02
  6. Step 6: Final answer
    x = 670.43

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Why These Related Problems?

These problems maintain the same ratio (1.37) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.