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Finding the Fourth Proportional to 77, 115.32 and 68.12

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Solution

The fourth proportional to 77, 115.32 and 68.12 is: 102.02

Step by Step Solution

  1. Step 1: Write the proportion equation
    77 : 115.32 = 68.12 : x
  2. Step 2: Convert to fraction form
    77/115.32 = 68.12/x
  3. Step 3: Cross multiply
    77x = 115.32 × 68.12
  4. Step 4: Simplify right side
    77x = 7,855.60
  5. Step 5: Solve for x
    x = 7,855.60/77
  6. Step 6: Final answer
    x = 102.02

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.