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Finding the Fourth Proportional to 258.08, 388.86 and 213.43

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Solution

The fourth proportional to 258.08, 388.86 and 213.43 is: 321.58

Step by Step Solution

  1. Step 1: Write the proportion equation
    258.08 : 388.86 = 213.43 : x
  2. Step 2: Convert to fraction form
    258.08/388.86 = 213.43/x
  3. Step 3: Cross multiply
    258.08x = 388.86 × 213.43
  4. Step 4: Simplify right side
    258.08x = 82,994.22
  5. Step 5: Solve for x
    x = 82,994.22/258.08
  6. Step 6: Final answer
    x = 321.58

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Why These Related Problems?

These problems maintain the same ratio (1.51) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.