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Finding the Fourth Proportional to 208.80, 288.25 and 138.96

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Solution

The fourth proportional to 208.80, 288.25 and 138.96 is: 191.83

Step by Step Solution

  1. Step 1: Write the proportion equation
    208.80 : 288.25 = 138.96 : x
  2. Step 2: Convert to fraction form
    208.80/288.25 = 138.96/x
  3. Step 3: Cross multiply
    208.80x = 288.25 × 138.96
  4. Step 4: Simplify right side
    208.80x = 40,054.87
  5. Step 5: Solve for x
    x = 40,054.87/208.80
  6. Step 6: Final answer
    x = 191.83

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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.