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Finding the Fourth Proportional to 86.30, 118.86 and 66.86

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Solution

The fourth proportional to 86.30, 118.86 and 66.86 is: 92.09

Step by Step Solution

  1. Step 1: Write the proportion equation
    86.30 : 118.86 = 66.86 : x
  2. Step 2: Convert to fraction form
    86.30/118.86 = 66.86/x
  3. Step 3: Cross multiply
    86.30x = 118.86 × 66.86
  4. Step 4: Simplify right side
    86.30x = 7,946.98
  5. Step 5: Solve for x
    x = 7,946.98/86.30
  6. Step 6: Final answer
    x = 92.09

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.