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Finding the Fourth Proportional to 489.90, 734.14 and 306.78

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Solution

The fourth proportional to 489.90, 734.14 and 306.78 is: 459.73

Step by Step Solution

  1. Step 1: Write the proportion equation
    489.90 : 734.14 = 306.78 : x
  2. Step 2: Convert to fraction form
    489.90/734.14 = 306.78/x
  3. Step 3: Cross multiply
    489.90x = 734.14 × 306.78
  4. Step 4: Simplify right side
    489.90x = 225,219.47
  5. Step 5: Solve for x
    x = 225,219.47/489.90
  6. Step 6: Final answer
    x = 459.73

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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.