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Finding the Fourth Proportional to 77.91, 116.29 and 68.90

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Solution

The fourth proportional to 77.91, 116.29 and 68.90 is: 102.84

Step by Step Solution

  1. Step 1: Write the proportion equation
    77.91 : 116.29 = 68.90 : x
  2. Step 2: Convert to fraction form
    77.91/116.29 = 68.90/x
  3. Step 3: Cross multiply
    77.91x = 116.29 × 68.90
  4. Step 4: Simplify right side
    77.91x = 8,012.38
  5. Step 5: Solve for x
    x = 8,012.38/77.91
  6. Step 6: Final answer
    x = 102.84

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.