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Finding the Fourth Proportional to 309.05, 426.83 and 210.63

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Solution

The fourth proportional to 309.05, 426.83 and 210.63 is: 290.90

Step by Step Solution

  1. Step 1: Write the proportion equation
    309.05 : 426.83 = 210.63 : x
  2. Step 2: Convert to fraction form
    309.05/426.83 = 210.63/x
  3. Step 3: Cross multiply
    309.05x = 426.83 × 210.63
  4. Step 4: Simplify right side
    309.05x = 89,902.15
  5. Step 5: Solve for x
    x = 89,902.15/309.05
  6. Step 6: Final answer
    x = 290.90

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.