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Finding the Fourth Proportional to 76.84, 105.47 and 68.20

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Solution

The fourth proportional to 76.84, 105.47 and 68.20 is: 93.61

Step by Step Solution

  1. Step 1: Write the proportion equation
    76.84 : 105.47 = 68.20 : x
  2. Step 2: Convert to fraction form
    76.84/105.47 = 68.20/x
  3. Step 3: Cross multiply
    76.84x = 105.47 × 68.20
  4. Step 4: Simplify right side
    76.84x = 7,193.05
  5. Step 5: Solve for x
    x = 7,193.05/76.84
  6. Step 6: Final answer
    x = 93.61

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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.