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Finding the Fourth Proportional to 85.19, 127.09 and 77.33

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Solution

The fourth proportional to 85.19, 127.09 and 77.33 is: 115.38

Step by Step Solution

  1. Step 1: Write the proportion equation
    85.19 : 127.09 = 77.33 : x
  2. Step 2: Convert to fraction form
    85.19/127.09 = 77.33/x
  3. Step 3: Cross multiply
    85.19x = 127.09 × 77.33
  4. Step 4: Simplify right side
    85.19x = 9,828.28
  5. Step 5: Solve for x
    x = 9,828.28/85.19
  6. Step 6: Final answer
    x = 115.38

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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.