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Finding the Fourth Proportional to 77.09, 115.47 and 68.49

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Solution

The fourth proportional to 77.09, 115.47 and 68.49 is: 102.60

Step by Step Solution

  1. Step 1: Write the proportion equation
    77.09 : 115.47 = 68.49 : x
  2. Step 2: Convert to fraction form
    77.09/115.47 = 68.49/x
  3. Step 3: Cross multiply
    77.09x = 115.47 × 68.49
  4. Step 4: Simplify right side
    77.09x = 7,908.54
  5. Step 5: Solve for x
    x = 7,908.54/77.09
  6. Step 6: Final answer
    x = 102.60

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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.