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Finding the Fourth Proportional to 309, 426.18 and 210.88

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Solution

The fourth proportional to 309, 426.18 and 210.88 is: 290.85

Step by Step Solution

  1. Step 1: Write the proportion equation
    309 : 426.18 = 210.88 : x
  2. Step 2: Convert to fraction form
    309/426.18 = 210.88/x
  3. Step 3: Cross multiply
    309x = 426.18 × 210.88
  4. Step 4: Simplify right side
    309x = 89,872.84
  5. Step 5: Solve for x
    x = 89,872.84/309
  6. Step 6: Final answer
    x = 290.85

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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.