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Finding the Fourth Proportional to 71.70, 107.56 and 69.72

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Solution

The fourth proportional to 71.70, 107.56 and 69.72 is: 104.59

Step by Step Solution

  1. Step 1: Write the proportion equation
    71.70 : 107.56 = 69.72 : x
  2. Step 2: Convert to fraction form
    71.70/107.56 = 69.72/x
  3. Step 3: Cross multiply
    71.70x = 107.56 × 69.72
  4. Step 4: Simplify right side
    71.70x = 7,499.08
  5. Step 5: Solve for x
    x = 7,499.08/71.70
  6. Step 6: Final answer
    x = 104.59

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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.