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Finding the Fourth Proportional to 258.60, 387.50 and 217.83

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Solution

The fourth proportional to 258.60, 387.50 and 217.83 is: 326.40

Step by Step Solution

  1. Step 1: Write the proportion equation
    258.60 : 387.50 = 217.83 : x
  2. Step 2: Convert to fraction form
    258.60/387.50 = 217.83/x
  3. Step 3: Cross multiply
    258.60x = 387.50 × 217.83
  4. Step 4: Simplify right side
    258.60x = 84,408.04
  5. Step 5: Solve for x
    x = 84,408.04/258.60
  6. Step 6: Final answer
    x = 326.40

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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.