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Finding the Fourth Proportional to 258.86, 388.29 and 204.79

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Solution

The fourth proportional to 258.86, 388.29 and 204.79 is: 307.19

Step by Step Solution

  1. Step 1: Write the proportion equation
    258.86 : 388.29 = 204.79 : x
  2. Step 2: Convert to fraction form
    258.86/388.29 = 204.79/x
  3. Step 3: Cross multiply
    258.86x = 388.29 × 204.79
  4. Step 4: Simplify right side
    258.86x = 79,517.91
  5. Step 5: Solve for x
    x = 79,517.91/258.86
  6. Step 6: Final answer
    x = 307.19

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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.