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Finding the Fourth Proportional to 71.48, 106.80 and 69.09

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Solution

The fourth proportional to 71.48, 106.80 and 69.09 is: 103.22

Step by Step Solution

  1. Step 1: Write the proportion equation
    71.48 : 106.80 = 69.09 : x
  2. Step 2: Convert to fraction form
    71.48/106.80 = 69.09/x
  3. Step 3: Cross multiply
    71.48x = 106.80 × 69.09
  4. Step 4: Simplify right side
    71.48x = 7,378.47
  5. Step 5: Solve for x
    x = 7,378.47/71.48
  6. Step 6: Final answer
    x = 103.22

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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.