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Finding the Fourth Proportional to 645.20, 967.80 and 255.18

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Solution

The fourth proportional to 645.20, 967.80 and 255.18 is: 382.77

Step by Step Solution

  1. Step 1: Write the proportion equation
    645.20 : 967.80 = 255.18 : x
  2. Step 2: Convert to fraction form
    645.20/967.80 = 255.18/x
  3. Step 3: Cross multiply
    645.20x = 967.80 × 255.18
  4. Step 4: Simplify right side
    645.20x = 246,962.57
  5. Step 5: Solve for x
    x = 246,962.57/645.20
  6. Step 6: Final answer
    x = 382.77

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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.