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Finding the Fourth Proportional to 77.00, 105.55 and 76.85

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Solution

The fourth proportional to 77.00, 105.55 and 76.85 is: 105.34

Step by Step Solution

  1. Step 1: Write the proportion equation
    77.00 : 105.55 = 76.85 : x
  2. Step 2: Convert to fraction form
    77.00/105.55 = 76.85/x
  3. Step 3: Cross multiply
    77.00x = 105.55 × 76.85
  4. Step 4: Simplify right side
    77.00x = 8,111.63
  5. Step 5: Solve for x
    x = 8,111.63/77.00
  6. Step 6: Final answer
    x = 105.34

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Why These Related Problems?

These problems maintain the same ratio (1.37) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.