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Finding the Fourth Proportional to 78.73, 108.67 and 47.65

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Solution

The fourth proportional to 78.73, 108.67 and 47.65 is: 65.77

Step by Step Solution

  1. Step 1: Write the proportion equation
    78.73 : 108.67 = 47.65 : x
  2. Step 2: Convert to fraction form
    78.73/108.67 = 47.65/x
  3. Step 3: Cross multiply
    78.73x = 108.67 × 47.65
  4. Step 4: Simplify right side
    78.73x = 5,178.05
  5. Step 5: Solve for x
    x = 5,178.05/78.73
  6. Step 6: Final answer
    x = 65.77

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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.