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Finding the Fourth Proportional to 77.14, 115.71 and 20.14

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Solution

The fourth proportional to 77.14, 115.71 and 20.14 is: 30.21

Step by Step Solution

  1. Step 1: Write the proportion equation
    77.14 : 115.71 = 20.14 : x
  2. Step 2: Convert to fraction form
    77.14/115.71 = 20.14/x
  3. Step 3: Cross multiply
    77.14x = 115.71 × 20.14
  4. Step 4: Simplify right side
    77.14x = 2,330.40
  5. Step 5: Solve for x
    x = 2,330.40/77.14
  6. Step 6: Final answer
    x = 30.21

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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.