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Finding the Fourth Proportional to 639.11, 958.26 and 419.46

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Solution

The fourth proportional to 639.11, 958.26 and 419.46 is: 628.93

Step by Step Solution

  1. Step 1: Write the proportion equation
    639.11 : 958.26 = 419.46 : x
  2. Step 2: Convert to fraction form
    639.11/958.26 = 419.46/x
  3. Step 3: Cross multiply
    639.11x = 958.26 × 419.46
  4. Step 4: Simplify right side
    639.11x = 401,949.64
  5. Step 5: Solve for x
    x = 401,949.64/639.11
  6. Step 6: Final answer
    x = 628.93

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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.