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Finding the Fourth Proportional to 71.09, 105.86 and 68.69

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Solution

The fourth proportional to 71.09, 105.86 and 68.69 is: 102.28

Step by Step Solution

  1. Step 1: Write the proportion equation
    71.09 : 105.86 = 68.69 : x
  2. Step 2: Convert to fraction form
    71.09/105.86 = 68.69/x
  3. Step 3: Cross multiply
    71.09x = 105.86 × 68.69
  4. Step 4: Simplify right side
    71.09x = 7,270.65
  5. Step 5: Solve for x
    x = 7,270.65/71.09
  6. Step 6: Final answer
    x = 102.28

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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.