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Finding the Fourth Proportional to 280.89, 387.34 and 218.61

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Solution

The fourth proportional to 280.89, 387.34 and 218.61 is: 301.46

Step by Step Solution

  1. Step 1: Write the proportion equation
    280.89 : 387.34 = 218.61 : x
  2. Step 2: Convert to fraction form
    280.89/387.34 = 218.61/x
  3. Step 3: Cross multiply
    280.89x = 387.34 × 218.61
  4. Step 4: Simplify right side
    280.89x = 84,676.40
  5. Step 5: Solve for x
    x = 84,676.40/280.89
  6. Step 6: Final answer
    x = 301.46

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.