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Finding the Fourth Proportional to 422.72, 634.38 and 340.71

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Solution

The fourth proportional to 422.72, 634.38 and 340.71 is: 511.31

Step by Step Solution

  1. Step 1: Write the proportion equation
    422.72 : 634.38 = 340.71 : x
  2. Step 2: Convert to fraction form
    422.72/634.38 = 340.71/x
  3. Step 3: Cross multiply
    422.72x = 634.38 × 340.71
  4. Step 4: Simplify right side
    422.72x = 216,139.61
  5. Step 5: Solve for x
    x = 216,139.61/422.72
  6. Step 6: Final answer
    x = 511.31

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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.