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Finding the Fourth Proportional to 101.08, 139.35 and 80.42

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Solution

The fourth proportional to 101.08, 139.35 and 80.42 is: 110.87

Step by Step Solution

  1. Step 1: Write the proportion equation
    101.08 : 139.35 = 80.42 : x
  2. Step 2: Convert to fraction form
    101.08/139.35 = 80.42/x
  3. Step 3: Cross multiply
    101.08x = 139.35 × 80.42
  4. Step 4: Simplify right side
    101.08x = 11,206.88
  5. Step 5: Solve for x
    x = 11,206.88/101.08
  6. Step 6: Final answer
    x = 110.87

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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.