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Finding the Fourth Proportional to 645.30, 968.10 and 280.38

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Solution

The fourth proportional to 645.30, 968.10 and 280.38 is: 420.64

Step by Step Solution

  1. Step 1: Write the proportion equation
    645.30 : 968.10 = 280.38 : x
  2. Step 2: Convert to fraction form
    645.30/968.10 = 280.38/x
  3. Step 3: Cross multiply
    645.30x = 968.10 × 280.38
  4. Step 4: Simplify right side
    645.30x = 271,435.88
  5. Step 5: Solve for x
    x = 271,435.88/645.30
  6. Step 6: Final answer
    x = 420.64

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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.