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Finding the Fourth Proportional to 208.05, 287.13 and 120.69

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Solution

The fourth proportional to 208.05, 287.13 and 120.69 is: 166.56

Step by Step Solution

  1. Step 1: Write the proportion equation
    208.05 : 287.13 = 120.69 : x
  2. Step 2: Convert to fraction form
    208.05/287.13 = 120.69/x
  3. Step 3: Cross multiply
    208.05x = 287.13 × 120.69
  4. Step 4: Simplify right side
    208.05x = 34,653.72
  5. Step 5: Solve for x
    x = 34,653.72/208.05
  6. Step 6: Final answer
    x = 166.56

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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.