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Finding the Fourth Proportional to 138.36, 208.55 and 131.32

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Solution

The fourth proportional to 138.36, 208.55 and 131.32 is: 197.94

Step by Step Solution

  1. Step 1: Write the proportion equation
    138.36 : 208.55 = 131.32 : x
  2. Step 2: Convert to fraction form
    138.36/208.55 = 131.32/x
  3. Step 3: Cross multiply
    138.36x = 208.55 × 131.32
  4. Step 4: Simplify right side
    138.36x = 27,386.79
  5. Step 5: Solve for x
    x = 27,386.79/138.36
  6. Step 6: Final answer
    x = 197.94

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Why These Related Problems?

These problems maintain the same ratio (1.51) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.