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Finding the Fourth Proportional to 212.05, 315.89 and 205.68

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Solution

The fourth proportional to 212.05, 315.89 and 205.68 is: 306.40

Step by Step Solution

  1. Step 1: Write the proportion equation
    212.05 : 315.89 = 205.68 : x
  2. Step 2: Convert to fraction form
    212.05/315.89 = 205.68/x
  3. Step 3: Cross multiply
    212.05x = 315.89 × 205.68
  4. Step 4: Simplify right side
    212.05x = 64,972.26
  5. Step 5: Solve for x
    x = 64,972.26/212.05
  6. Step 6: Final answer
    x = 306.40

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.