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Finding the Fourth Proportional to 258.85, 388.68 and 204.99

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Solution

The fourth proportional to 258.85, 388.68 and 204.99 is: 307.81

Step by Step Solution

  1. Step 1: Write the proportion equation
    258.85 : 388.68 = 204.99 : x
  2. Step 2: Convert to fraction form
    258.85/388.68 = 204.99/x
  3. Step 3: Cross multiply
    258.85x = 388.68 × 204.99
  4. Step 4: Simplify right side
    258.85x = 79,675.51
  5. Step 5: Solve for x
    x = 79,675.51/258.85
  6. Step 6: Final answer
    x = 307.81

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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.