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Finding the Fourth Proportional to 208.39, 287.49 and 142.87

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Solution

The fourth proportional to 208.39, 287.49 and 142.87 is: 197.10

Step by Step Solution

  1. Step 1: Write the proportion equation
    208.39 : 287.49 = 142.87 : x
  2. Step 2: Convert to fraction form
    208.39/287.49 = 142.87/x
  3. Step 3: Cross multiply
    208.39x = 287.49 × 142.87
  4. Step 4: Simplify right side
    208.39x = 41,073.70
  5. Step 5: Solve for x
    x = 41,073.70/208.39
  6. Step 6: Final answer
    x = 197.10

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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.