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Finding the Fourth Proportional to 100.07, 137.97 and 81.61

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Solution

The fourth proportional to 100.07, 137.97 and 81.61 is: 112.52

Step by Step Solution

  1. Step 1: Write the proportion equation
    100.07 : 137.97 = 81.61 : x
  2. Step 2: Convert to fraction form
    100.07/137.97 = 81.61/x
  3. Step 3: Cross multiply
    100.07x = 137.97 × 81.61
  4. Step 4: Simplify right side
    100.07x = 11,259.39
  5. Step 5: Solve for x
    x = 11,259.39/100.07
  6. Step 6: Final answer
    x = 112.52

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.