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Finding the Fourth Proportional to 280.54, 421.42 and 199.90

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Solution

The fourth proportional to 280.54, 421.42 and 199.90 is: 300.28

Step by Step Solution

  1. Step 1: Write the proportion equation
    280.54 : 421.42 = 199.90 : x
  2. Step 2: Convert to fraction form
    280.54/421.42 = 199.90/x
  3. Step 3: Cross multiply
    280.54x = 421.42 × 199.90
  4. Step 4: Simplify right side
    280.54x = 84,241.86
  5. Step 5: Solve for x
    x = 84,241.86/280.54
  6. Step 6: Final answer
    x = 300.28

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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.