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Finding the Fourth Proportional to 77.45, 116.78 and 68.54

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Solution

The fourth proportional to 77.45, 116.78 and 68.54 is: 103.34

Step by Step Solution

  1. Step 1: Write the proportion equation
    77.45 : 116.78 = 68.54 : x
  2. Step 2: Convert to fraction form
    77.45/116.78 = 68.54/x
  3. Step 3: Cross multiply
    77.45x = 116.78 × 68.54
  4. Step 4: Simplify right side
    77.45x = 8,003.17
  5. Step 5: Solve for x
    x = 8,003.17/77.45
  6. Step 6: Final answer
    x = 103.34

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Why These Related Problems?

These problems maintain the same ratio (1.51) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.