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Finding the Fourth Proportional to 305.82, 422.11 and 189.31

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Solution

The fourth proportional to 305.82, 422.11 and 189.31 is: 261.30

Step by Step Solution

  1. Step 1: Write the proportion equation
    305.82 : 422.11 = 189.31 : x
  2. Step 2: Convert to fraction form
    305.82/422.11 = 189.31/x
  3. Step 3: Cross multiply
    305.82x = 422.11 × 189.31
  4. Step 4: Simplify right side
    305.82x = 79,909.64
  5. Step 5: Solve for x
    x = 79,909.64/305.82
  6. Step 6: Final answer
    x = 261.30

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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.