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Finding the Fourth Proportional to 378.89, 522.87 and 213.12

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Solution

The fourth proportional to 378.89, 522.87 and 213.12 is: 294.11

Step by Step Solution

  1. Step 1: Write the proportion equation
    378.89 : 522.87 = 213.12 : x
  2. Step 2: Convert to fraction form
    378.89/522.87 = 213.12/x
  3. Step 3: Cross multiply
    378.89x = 522.87 × 213.12
  4. Step 4: Simplify right side
    378.89x = 111,434.05
  5. Step 5: Solve for x
    x = 111,434.05/378.89
  6. Step 6: Final answer
    x = 294.11

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.