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Finding the Fourth Proportional to 85.14, 127.06 and 77.13

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Solution

The fourth proportional to 85.14, 127.06 and 77.13 is: 115.10

Step by Step Solution

  1. Step 1: Write the proportion equation
    85.14 : 127.06 = 77.13 : x
  2. Step 2: Convert to fraction form
    85.14/127.06 = 77.13/x
  3. Step 3: Cross multiply
    85.14x = 127.06 × 77.13
  4. Step 4: Simplify right side
    85.14x = 9,799.94
  5. Step 5: Solve for x
    x = 9,799.94/85.14
  6. Step 6: Final answer
    x = 115.10

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.