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Finding the Fourth Proportional to 422.90, 634.30 and 145.22

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Solution

The fourth proportional to 422.90, 634.30 and 145.22 is: 217.81

Step by Step Solution

  1. Step 1: Write the proportion equation
    422.90 : 634.30 = 145.22 : x
  2. Step 2: Convert to fraction form
    422.90/634.30 = 145.22/x
  3. Step 3: Cross multiply
    422.90x = 634.30 × 145.22
  4. Step 4: Simplify right side
    422.90x = 92,113.05
  5. Step 5: Solve for x
    x = 92,113.05/422.90
  6. Step 6: Final answer
    x = 217.81

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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.