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Finding the Fourth Proportional to 342.78, 512.97 and 212.70

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Solution

The fourth proportional to 342.78, 512.97 and 212.70 is: 318.31

Step by Step Solution

  1. Step 1: Write the proportion equation
    342.78 : 512.97 = 212.70 : x
  2. Step 2: Convert to fraction form
    342.78/512.97 = 212.70/x
  3. Step 3: Cross multiply
    342.78x = 512.97 × 212.70
  4. Step 4: Simplify right side
    342.78x = 109,108.72
  5. Step 5: Solve for x
    x = 109,108.72/342.78
  6. Step 6: Final answer
    x = 318.31

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.