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Finding the Fourth Proportional to 378.65, 522.47 and 212.85

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Solution

The fourth proportional to 378.65, 522.47 and 212.85 is: 293.70

Step by Step Solution

  1. Step 1: Write the proportion equation
    378.65 : 522.47 = 212.85 : x
  2. Step 2: Convert to fraction form
    378.65/522.47 = 212.85/x
  3. Step 3: Cross multiply
    378.65x = 522.47 × 212.85
  4. Step 4: Simplify right side
    378.65x = 111,206.68
  5. Step 5: Solve for x
    x = 111,206.68/378.65
  6. Step 6: Final answer
    x = 293.70

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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.