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Finding the Fourth Proportional to 497.15, 690.56 and 489.20

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Solution

The fourth proportional to 497.15, 690.56 and 489.20 is: 679.52

Step by Step Solution

  1. Step 1: Write the proportion equation
    497.15 : 690.56 = 489.20 : x
  2. Step 2: Convert to fraction form
    497.15/690.56 = 489.20/x
  3. Step 3: Cross multiply
    497.15x = 690.56 × 489.20
  4. Step 4: Simplify right side
    497.15x = 337,821.96
  5. Step 5: Solve for x
    x = 337,821.96/497.15
  6. Step 6: Final answer
    x = 679.52

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Why These Related Problems?

These problems maintain the same ratio (1.39) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.