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Finding the Fourth Proportional to 290.20, 434.82 and 212.80

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Solution

The fourth proportional to 290.20, 434.82 and 212.80 is: 318.85

Step by Step Solution

  1. Step 1: Write the proportion equation
    290.20 : 434.82 = 212.80 : x
  2. Step 2: Convert to fraction form
    290.20/434.82 = 212.80/x
  3. Step 3: Cross multiply
    290.20x = 434.82 × 212.80
  4. Step 4: Simplify right side
    290.20x = 92,529.70
  5. Step 5: Solve for x
    x = 92,529.70/290.20
  6. Step 6: Final answer
    x = 318.85

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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.