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Finding the Fourth Proportional to 645.55, 968.73 and 280.26

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Solution

The fourth proportional to 645.55, 968.73 and 280.26 is: 420.56

Step by Step Solution

  1. Step 1: Write the proportion equation
    645.55 : 968.73 = 280.26 : x
  2. Step 2: Convert to fraction form
    645.55/968.73 = 280.26/x
  3. Step 3: Cross multiply
    645.55x = 968.73 × 280.26
  4. Step 4: Simplify right side
    645.55x = 271,490.02
  5. Step 5: Solve for x
    x = 271,490.02/645.55
  6. Step 6: Final answer
    x = 420.56

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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.