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Finding the Fourth Proportional to 280.56, 387.68 and 218.55

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Solution

The fourth proportional to 280.56, 387.68 and 218.55 is: 301.99

Step by Step Solution

  1. Step 1: Write the proportion equation
    280.56 : 387.68 = 218.55 : x
  2. Step 2: Convert to fraction form
    280.56/387.68 = 218.55/x
  3. Step 3: Cross multiply
    280.56x = 387.68 × 218.55
  4. Step 4: Simplify right side
    280.56x = 84,726.37
  5. Step 5: Solve for x
    x = 84,726.37/280.56
  6. Step 6: Final answer
    x = 301.99

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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.