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Finding the Fourth Proportional to 171.09, 256.80 and 138.62

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Solution

The fourth proportional to 171.09, 256.80 and 138.62 is: 208.06

Step by Step Solution

  1. Step 1: Write the proportion equation
    171.09 : 256.80 = 138.62 : x
  2. Step 2: Convert to fraction form
    171.09/256.80 = 138.62/x
  3. Step 3: Cross multiply
    171.09x = 256.80 × 138.62
  4. Step 4: Simplify right side
    171.09x = 35,596.33
  5. Step 5: Solve for x
    x = 35,596.33/171.09
  6. Step 6: Final answer
    x = 208.06

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.