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Finding the Fourth Proportional to 280.89, 420.77 and 144.05

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Solution

The fourth proportional to 280.89, 420.77 and 144.05 is: 215.78

Step by Step Solution

  1. Step 1: Write the proportion equation
    280.89 : 420.77 = 144.05 : x
  2. Step 2: Convert to fraction form
    280.89/420.77 = 144.05/x
  3. Step 3: Cross multiply
    280.89x = 420.77 × 144.05
  4. Step 4: Simplify right side
    280.89x = 60,610.17
  5. Step 5: Solve for x
    x = 60,610.17/280.89
  6. Step 6: Final answer
    x = 215.78

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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.