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Finding the Fourth Proportional to 171.87, 257.91 and 69.21

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Solution

The fourth proportional to 171.87, 257.91 and 69.21 is: 103.86

Step by Step Solution

  1. Step 1: Write the proportion equation
    171.87 : 257.91 = 69.21 : x
  2. Step 2: Convert to fraction form
    171.87/257.91 = 69.21/x
  3. Step 3: Cross multiply
    171.87x = 257.91 × 69.21
  4. Step 4: Simplify right side
    171.87x = 17,849.95
  5. Step 5: Solve for x
    x = 17,849.95/171.87
  6. Step 6: Final answer
    x = 103.86

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