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Finding the Fourth Proportional to 91.02, 125.15 and 81.09

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Solution

The fourth proportional to 91.02, 125.15 and 81.09 is: 111.49

Step by Step Solution

  1. Step 1: Write the proportion equation
    91.02 : 125.15 = 81.09 : x
  2. Step 2: Convert to fraction form
    91.02/125.15 = 81.09/x
  3. Step 3: Cross multiply
    91.02x = 125.15 × 81.09
  4. Step 4: Simplify right side
    91.02x = 10,148.01
  5. Step 5: Solve for x
    x = 10,148.01/91.02
  6. Step 6: Final answer
    x = 111.49

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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.