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Finding the Fourth Proportional to 77.08, 105.80 and 69.79

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Solution

The fourth proportional to 77.08, 105.80 and 69.79 is: 95.79

Step by Step Solution

  1. Step 1: Write the proportion equation
    77.08 : 105.80 = 69.79 : x
  2. Step 2: Convert to fraction form
    77.08/105.80 = 69.79/x
  3. Step 3: Cross multiply
    77.08x = 105.80 × 69.79
  4. Step 4: Simplify right side
    77.08x = 7,383.78
  5. Step 5: Solve for x
    x = 7,383.78/77.08
  6. Step 6: Final answer
    x = 95.79

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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.