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Finding the Fourth Proportional to 257.29, 386.30 and 205.99

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Solution

The fourth proportional to 257.29, 386.30 and 205.99 is: 309.28

Step by Step Solution

  1. Step 1: Write the proportion equation
    257.29 : 386.30 = 205.99 : x
  2. Step 2: Convert to fraction form
    257.29/386.30 = 205.99/x
  3. Step 3: Cross multiply
    257.29x = 386.30 × 205.99
  4. Step 4: Simplify right side
    257.29x = 79,573.49
  5. Step 5: Solve for x
    x = 79,573.49/257.29
  6. Step 6: Final answer
    x = 309.28

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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.