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Finding the Fourth Proportional to 86.85, 129.96 and 69.03

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Solution

The fourth proportional to 86.85, 129.96 and 69.03 is: 103.29

Step by Step Solution

  1. Step 1: Write the proportion equation
    86.85 : 129.96 = 69.03 : x
  2. Step 2: Convert to fraction form
    86.85/129.96 = 69.03/x
  3. Step 3: Cross multiply
    86.85x = 129.96 × 69.03
  4. Step 4: Simplify right side
    86.85x = 8,971.14
  5. Step 5: Solve for x
    x = 8,971.14/86.85
  6. Step 6: Final answer
    x = 103.29

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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.