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Finding the Fourth Proportional to 422.87, 629.15 and 421.43

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Solution

The fourth proportional to 422.87, 629.15 and 421.43 is: 627.00

Step by Step Solution

  1. Step 1: Write the proportion equation
    422.87 : 629.15 = 421.43 : x
  2. Step 2: Convert to fraction form
    422.87/629.15 = 421.43/x
  3. Step 3: Cross multiply
    422.87x = 629.15 × 421.43
  4. Step 4: Simplify right side
    422.87x = 265,137.43
  5. Step 5: Solve for x
    x = 265,137.43/422.87
  6. Step 6: Final answer
    x = 627.00

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.