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Finding the Fourth Proportional to 422.30, 581.91 and 311.60

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Solution

The fourth proportional to 422.30, 581.91 and 311.60 is: 429.37

Step by Step Solution

  1. Step 1: Write the proportion equation
    422.30 : 581.91 = 311.60 : x
  2. Step 2: Convert to fraction form
    422.30/581.91 = 311.60/x
  3. Step 3: Cross multiply
    422.30x = 581.91 × 311.60
  4. Step 4: Simplify right side
    422.30x = 181,323.16
  5. Step 5: Solve for x
    x = 181,323.16/422.30
  6. Step 6: Final answer
    x = 429.37

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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.