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Finding the Fourth Proportional to 388.20, 535.72 and 213.56

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Solution

The fourth proportional to 388.20, 535.72 and 213.56 is: 294.72

Step by Step Solution

  1. Step 1: Write the proportion equation
    388.20 : 535.72 = 213.56 : x
  2. Step 2: Convert to fraction form
    388.20/535.72 = 213.56/x
  3. Step 3: Cross multiply
    388.20x = 535.72 × 213.56
  4. Step 4: Simplify right side
    388.20x = 114,408.36
  5. Step 5: Solve for x
    x = 114,408.36/388.20
  6. Step 6: Final answer
    x = 294.72

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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.