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Finding the Fourth Proportional to 305.91, 422.36 and 212.85

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Solution

The fourth proportional to 305.91, 422.36 and 212.85 is: 293.88

Step by Step Solution

  1. Step 1: Write the proportion equation
    305.91 : 422.36 = 212.85 : x
  2. Step 2: Convert to fraction form
    305.91/422.36 = 212.85/x
  3. Step 3: Cross multiply
    305.91x = 422.36 × 212.85
  4. Step 4: Simplify right side
    305.91x = 89,901.45
  5. Step 5: Solve for x
    x = 89,901.45/305.91
  6. Step 6: Final answer
    x = 293.88

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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.