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Finding the Fourth Proportional to 206.07, 309.15 and 145.05

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Solution

The fourth proportional to 206.07, 309.15 and 145.05 is: 217.61

Step by Step Solution

  1. Step 1: Write the proportion equation
    206.07 : 309.15 = 145.05 : x
  2. Step 2: Convert to fraction form
    206.07/309.15 = 145.05/x
  3. Step 3: Cross multiply
    206.07x = 309.15 × 145.05
  4. Step 4: Simplify right side
    206.07x = 44,842.21
  5. Step 5: Solve for x
    x = 44,842.21/206.07
  6. Step 6: Final answer
    x = 217.61

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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.