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Finding the Fourth Proportional to 489.86, 735.12 and 215.80

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Solution

The fourth proportional to 489.86, 735.12 and 215.80 is: 323.85

Step by Step Solution

  1. Step 1: Write the proportion equation
    489.86 : 735.12 = 215.80 : x
  2. Step 2: Convert to fraction form
    489.86/735.12 = 215.80/x
  3. Step 3: Cross multiply
    489.86x = 735.12 × 215.80
  4. Step 4: Simplify right side
    489.86x = 158,638.90
  5. Step 5: Solve for x
    x = 158,638.90/489.86
  6. Step 6: Final answer
    x = 323.85

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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.