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Finding the Fourth Proportional to 209.09, 313.46 and 80.75

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Solution

The fourth proportional to 209.09, 313.46 and 80.75 is: 121.06

Step by Step Solution

  1. Step 1: Write the proportion equation
    209.09 : 313.46 = 80.75 : x
  2. Step 2: Convert to fraction form
    209.09/313.46 = 80.75/x
  3. Step 3: Cross multiply
    209.09x = 313.46 × 80.75
  4. Step 4: Simplify right side
    209.09x = 25,311.49
  5. Step 5: Solve for x
    x = 25,311.49/209.09
  6. Step 6: Final answer
    x = 121.06

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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.