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Finding the Fourth Proportional to 205.99, 309.09 and 145.00

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Solution

The fourth proportional to 205.99, 309.09 and 145.00 is: 217.57

Step by Step Solution

  1. Step 1: Write the proportion equation
    205.99 : 309.09 = 145.00 : x
  2. Step 2: Convert to fraction form
    205.99/309.09 = 145.00/x
  3. Step 3: Cross multiply
    205.99x = 309.09 × 145.00
  4. Step 4: Simplify right side
    205.99x = 44,815.78
  5. Step 5: Solve for x
    x = 44,815.78/205.99
  6. Step 6: Final answer
    x = 217.57

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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.