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Finding the Fourth Proportional to 84.40, 115.56 and 81.33

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Solution

The fourth proportional to 84.40, 115.56 and 81.33 is: 111.35

Step by Step Solution

  1. Step 1: Write the proportion equation
    84.40 : 115.56 = 81.33 : x
  2. Step 2: Convert to fraction form
    84.40/115.56 = 81.33/x
  3. Step 3: Cross multiply
    84.40x = 115.56 × 81.33
  4. Step 4: Simplify right side
    84.40x = 9,398.21
  5. Step 5: Solve for x
    x = 9,398.21/84.40
  6. Step 6: Final answer
    x = 111.35

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Why These Related Problems?

These problems maintain the same ratio (1.37) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.