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Finding the Fourth Proportional to 208.64, 287.86 and 120.12

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Solution

The fourth proportional to 208.64, 287.86 and 120.12 is: 165.73

Step by Step Solution

  1. Step 1: Write the proportion equation
    208.64 : 287.86 = 120.12 : x
  2. Step 2: Convert to fraction form
    208.64/287.86 = 120.12/x
  3. Step 3: Cross multiply
    208.64x = 287.86 × 120.12
  4. Step 4: Simplify right side
    208.64x = 34,577.74
  5. Step 5: Solve for x
    x = 34,577.74/208.64
  6. Step 6: Final answer
    x = 165.73

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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.