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Finding the Fourth Proportional to 70.60, 105.12 and 68.70

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Solution

The fourth proportional to 70.60, 105.12 and 68.70 is: 102.29

Step by Step Solution

  1. Step 1: Write the proportion equation
    70.60 : 105.12 = 68.70 : x
  2. Step 2: Convert to fraction form
    70.60/105.12 = 68.70/x
  3. Step 3: Cross multiply
    70.60x = 105.12 × 68.70
  4. Step 4: Simplify right side
    70.60x = 7,221.74
  5. Step 5: Solve for x
    x = 7,221.74/70.60
  6. Step 6: Final answer
    x = 102.29

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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.