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Finding the Fourth Proportional to 81.79, 112.97 and 54.16

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Solution

The fourth proportional to 81.79, 112.97 and 54.16 is: 74.81

Step by Step Solution

  1. Step 1: Write the proportion equation
    81.79 : 112.97 = 54.16 : x
  2. Step 2: Convert to fraction form
    81.79/112.97 = 54.16/x
  3. Step 3: Cross multiply
    81.79x = 112.97 × 54.16
  4. Step 4: Simplify right side
    81.79x = 6,118.46
  5. Step 5: Solve for x
    x = 6,118.46/81.79
  6. Step 6: Final answer
    x = 74.81

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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.