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Finding the Fourth Proportional to 258.41, 387.12 and 212.39

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Solution

The fourth proportional to 258.41, 387.12 and 212.39 is: 318.18

Step by Step Solution

  1. Step 1: Write the proportion equation
    258.41 : 387.12 = 212.39 : x
  2. Step 2: Convert to fraction form
    258.41/387.12 = 212.39/x
  3. Step 3: Cross multiply
    258.41x = 387.12 × 212.39
  4. Step 4: Simplify right side
    258.41x = 82,220.42
  5. Step 5: Solve for x
    x = 82,220.42/258.41
  6. Step 6: Final answer
    x = 318.18

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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.