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Finding the Fourth Proportional to 78.11, 107.85 and 55.98

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Solution

The fourth proportional to 78.11, 107.85 and 55.98 is: 77.29

Step by Step Solution

  1. Step 1: Write the proportion equation
    78.11 : 107.85 = 55.98 : x
  2. Step 2: Convert to fraction form
    78.11/107.85 = 55.98/x
  3. Step 3: Cross multiply
    78.11x = 107.85 × 55.98
  4. Step 4: Simplify right side
    78.11x = 6,037.44
  5. Step 5: Solve for x
    x = 6,037.44/78.11
  6. Step 6: Final answer
    x = 77.29

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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.