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Finding the Fourth Proportional to 645.62, 968.76 and 280.66

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Solution

The fourth proportional to 645.62, 968.76 and 280.66 is: 421.14

Step by Step Solution

  1. Step 1: Write the proportion equation
    645.62 : 968.76 = 280.66 : x
  2. Step 2: Convert to fraction form
    645.62/968.76 = 280.66/x
  3. Step 3: Cross multiply
    645.62x = 968.76 × 280.66
  4. Step 4: Simplify right side
    645.62x = 271,892.18
  5. Step 5: Solve for x
    x = 271,892.18/645.62
  6. Step 6: Final answer
    x = 421.14

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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.