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Finding the Fourth Proportional to 138.88, 206.84 and 138.07

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Solution

The fourth proportional to 138.88, 206.84 and 138.07 is: 205.63

Step by Step Solution

  1. Step 1: Write the proportion equation
    138.88 : 206.84 = 138.07 : x
  2. Step 2: Convert to fraction form
    138.88/206.84 = 138.07/x
  3. Step 3: Cross multiply
    138.88x = 206.84 × 138.07
  4. Step 4: Simplify right side
    138.88x = 28,558.40
  5. Step 5: Solve for x
    x = 28,558.40/138.88
  6. Step 6: Final answer
    x = 205.63

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.