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Finding the Fourth Proportional to 78.21, 107.94 and 62.73

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Solution

The fourth proportional to 78.21, 107.94 and 62.73 is: 86.58

Step by Step Solution

  1. Step 1: Write the proportion equation
    78.21 : 107.94 = 62.73 : x
  2. Step 2: Convert to fraction form
    78.21/107.94 = 62.73/x
  3. Step 3: Cross multiply
    78.21x = 107.94 × 62.73
  4. Step 4: Simplify right side
    78.21x = 6,771.08
  5. Step 5: Solve for x
    x = 6,771.08/78.21
  6. Step 6: Final answer
    x = 86.58

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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.