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Finding the Fourth Proportional to 378.39, 522.20 and 212.57

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Solution

The fourth proportional to 378.39, 522.20 and 212.57 is: 293.35

Step by Step Solution

  1. Step 1: Write the proportion equation
    378.39 : 522.20 = 212.57 : x
  2. Step 2: Convert to fraction form
    378.39/522.20 = 212.57/x
  3. Step 3: Cross multiply
    378.39x = 522.20 × 212.57
  4. Step 4: Simplify right side
    378.39x = 111,002.74
  5. Step 5: Solve for x
    x = 111,002.74/378.39
  6. Step 6: Final answer
    x = 293.35

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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.