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Finding the Fourth Proportional to 101.40, 138.81 and 98.30

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Solution

The fourth proportional to 101.40, 138.81 and 98.30 is: 134.56

Step by Step Solution

  1. Step 1: Write the proportion equation
    101.40 : 138.81 = 98.30 : x
  2. Step 2: Convert to fraction form
    101.40/138.81 = 98.30/x
  3. Step 3: Cross multiply
    101.40x = 138.81 × 98.30
  4. Step 4: Simplify right side
    101.40x = 13,644.33
  5. Step 5: Solve for x
    x = 13,644.33/101.40
  6. Step 6: Final answer
    x = 134.56

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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.