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Finding the Fourth Proportional to 71.22, 98.79 and 68.70

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Solution

The fourth proportional to 71.22, 98.79 and 68.70 is: 95.29

Step by Step Solution

  1. Step 1: Write the proportion equation
    71.22 : 98.79 = 68.70 : x
  2. Step 2: Convert to fraction form
    71.22/98.79 = 68.70/x
  3. Step 3: Cross multiply
    71.22x = 98.79 × 68.70
  4. Step 4: Simplify right side
    71.22x = 6,786.87
  5. Step 5: Solve for x
    x = 6,786.87/71.22
  6. Step 6: Final answer
    x = 95.29

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Why These Related Problems?

These problems maintain the same ratio (1.39) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.