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Finding the Fourth Proportional to 86.15, 129.25 and 83.06

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Solution

The fourth proportional to 86.15, 129.25 and 83.06 is: 124.61

Step by Step Solution

  1. Step 1: Write the proportion equation
    86.15 : 129.25 = 83.06 : x
  2. Step 2: Convert to fraction form
    86.15/129.25 = 83.06/x
  3. Step 3: Cross multiply
    86.15x = 129.25 × 83.06
  4. Step 4: Simplify right side
    86.15x = 10,735.51
  5. Step 5: Solve for x
    x = 10,735.51/86.15
  6. Step 6: Final answer
    x = 124.61

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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.