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Finding the Fourth Proportional to 489.35, 674.72 and 395.80

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Solution

The fourth proportional to 489.35, 674.72 and 395.80 is: 545.73

Step by Step Solution

  1. Step 1: Write the proportion equation
    489.35 : 674.72 = 395.80 : x
  2. Step 2: Convert to fraction form
    489.35/674.72 = 395.80/x
  3. Step 3: Cross multiply
    489.35x = 674.72 × 395.80
  4. Step 4: Simplify right side
    489.35x = 267,054.18
  5. Step 5: Solve for x
    x = 267,054.18/489.35
  6. Step 6: Final answer
    x = 545.73

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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.