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Finding the Fourth Proportional to 280.98, 387.57 and 218.70

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Solution

The fourth proportional to 280.98, 387.57 and 218.70 is: 301.66

Step by Step Solution

  1. Step 1: Write the proportion equation
    280.98 : 387.57 = 218.70 : x
  2. Step 2: Convert to fraction form
    280.98/387.57 = 218.70/x
  3. Step 3: Cross multiply
    280.98x = 387.57 × 218.70
  4. Step 4: Simplify right side
    280.98x = 84,761.56
  5. Step 5: Solve for x
    x = 84,761.56/280.98
  6. Step 6: Final answer
    x = 301.66

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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.