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Finding the Fourth Proportional to 103.82, 142.43 and 100.85

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Solution

The fourth proportional to 103.82, 142.43 and 100.85 is: 138.35

Step by Step Solution

  1. Step 1: Write the proportion equation
    103.82 : 142.43 = 100.85 : x
  2. Step 2: Convert to fraction form
    103.82/142.43 = 100.85/x
  3. Step 3: Cross multiply
    103.82x = 142.43 × 100.85
  4. Step 4: Simplify right side
    103.82x = 14,362.85
  5. Step 5: Solve for x
    x = 14,362.85/103.82
  6. Step 6: Final answer
    x = 138.35

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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.