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Finding the Fourth Proportional to 208.19, 287.27 and 120.85

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Solution

The fourth proportional to 208.19, 287.27 and 120.85 is: 166.75

Step by Step Solution

  1. Step 1: Write the proportion equation
    208.19 : 287.27 = 120.85 : x
  2. Step 2: Convert to fraction form
    208.19/287.27 = 120.85/x
  3. Step 3: Cross multiply
    208.19x = 287.27 × 120.85
  4. Step 4: Simplify right side
    208.19x = 34,716.58
  5. Step 5: Solve for x
    x = 34,716.58/208.19
  6. Step 6: Final answer
    x = 166.75

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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.