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Finding the Fourth Proportional to 81.19, 121.56 and 63.19

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Solution

The fourth proportional to 81.19, 121.56 and 63.19 is: 94.61

Step by Step Solution

  1. Step 1: Write the proportion equation
    81.19 : 121.56 = 63.19 : x
  2. Step 2: Convert to fraction form
    81.19/121.56 = 63.19/x
  3. Step 3: Cross multiply
    81.19x = 121.56 × 63.19
  4. Step 4: Simplify right side
    81.19x = 7,681.38
  5. Step 5: Solve for x
    x = 7,681.38/81.19
  6. Step 6: Final answer
    x = 94.61

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.