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Finding the Fourth Proportional to 78.94, 108.94 and 47.85

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Solution

The fourth proportional to 78.94, 108.94 and 47.85 is: 66.03

Step by Step Solution

  1. Step 1: Write the proportion equation
    78.94 : 108.94 = 47.85 : x
  2. Step 2: Convert to fraction form
    78.94/108.94 = 47.85/x
  3. Step 3: Cross multiply
    78.94x = 108.94 × 47.85
  4. Step 4: Simplify right side
    78.94x = 5,212.51
  5. Step 5: Solve for x
    x = 5,212.51/78.94
  6. Step 6: Final answer
    x = 66.03

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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.