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Finding the Fourth Proportional to 70.39, 105.71 and 68.86

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Solution

The fourth proportional to 70.39, 105.71 and 68.86 is: 103.41

Step by Step Solution

  1. Step 1: Write the proportion equation
    70.39 : 105.71 = 68.86 : x
  2. Step 2: Convert to fraction form
    70.39/105.71 = 68.86/x
  3. Step 3: Cross multiply
    70.39x = 105.71 × 68.86
  4. Step 4: Simplify right side
    70.39x = 7,279.19
  5. Step 5: Solve for x
    x = 7,279.19/70.39
  6. Step 6: Final answer
    x = 103.41

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.