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Finding the Fourth Proportional to 171.45, 257.25 and 80.20

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Solution

The fourth proportional to 171.45, 257.25 and 80.20 is: 120.34

Step by Step Solution

  1. Step 1: Write the proportion equation
    171.45 : 257.25 = 80.20 : x
  2. Step 2: Convert to fraction form
    171.45/257.25 = 80.20/x
  3. Step 3: Cross multiply
    171.45x = 257.25 × 80.20
  4. Step 4: Simplify right side
    171.45x = 20,632.10
  5. Step 5: Solve for x
    x = 20,632.10/171.45
  6. Step 6: Final answer
    x = 120.34

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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.