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Finding the Fourth Proportional to 645.17, 968.20 and 280.06

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Solution

The fourth proportional to 645.17, 968.20 and 280.06 is: 420.28

Step by Step Solution

  1. Step 1: Write the proportion equation
    645.17 : 968.20 = 280.06 : x
  2. Step 2: Convert to fraction form
    645.17/968.20 = 280.06/x
  3. Step 3: Cross multiply
    645.17x = 968.20 × 280.06
  4. Step 4: Simplify right side
    645.17x = 271,152.55
  5. Step 5: Solve for x
    x = 271,152.55/645.17
  6. Step 6: Final answer
    x = 420.28

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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.