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Finding the Fourth Proportional to 70.52, 105.80 and 68.80

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Solution

The fourth proportional to 70.52, 105.80 and 68.80 is: 103.22

Step by Step Solution

  1. Step 1: Write the proportion equation
    70.52 : 105.80 = 68.80 : x
  2. Step 2: Convert to fraction form
    70.52/105.80 = 68.80/x
  3. Step 3: Cross multiply
    70.52x = 105.80 × 68.80
  4. Step 4: Simplify right side
    70.52x = 7,279.04
  5. Step 5: Solve for x
    x = 7,279.04/70.52
  6. Step 6: Final answer
    x = 103.22

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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.