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Finding the Third Proportional to 218.06 and 311.81

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Solution

The third proportional to 218.06 and 311.81 is: 445.87

Step by Step Solution

  1. Step 1: Write the proportion equation
    218.06 : 311.81 = 311.81 : x
  2. Step 2: Convert to fraction form
    218.06/311.81 = 311.81/x
  3. Step 3: Cross multiply
    218.06x = 311.81 × 311.81
  4. Step 4: Simplify right side
    218.06x = 97,227.04
  5. Step 5: Solve for x
    x = 97,227.04/218.06
  6. Step 6: Final answer
    x = 445.87

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Why These Related Problems?

These problems maintain the same ratio (1.43) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.