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Finding the Fourth Proportional to 78.92, 109.08 and 62.66

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Solution

The fourth proportional to 78.92, 109.08 and 62.66 is: 86.61

Step by Step Solution

  1. Step 1: Write the proportion equation
    78.92 : 109.08 = 62.66 : x
  2. Step 2: Convert to fraction form
    78.92/109.08 = 62.66/x
  3. Step 3: Cross multiply
    78.92x = 109.08 × 62.66
  4. Step 4: Simplify right side
    78.92x = 6,834.95
  5. Step 5: Solve for x
    x = 6,834.95/78.92
  6. Step 6: Final answer
    x = 86.61

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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.