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Finding the Fourth Proportional to 669.26, 1,003.11 and 419.21

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Solution

The fourth proportional to 669.26, 1,003.11 and 419.21 is: 628.33

Step by Step Solution

  1. Step 1: Write the proportion equation
    669.26 : 1,003.11 = 419.21 : x
  2. Step 2: Convert to fraction form
    669.26/1,003.11 = 419.21/x
  3. Step 3: Cross multiply
    669.26x = 1,003.11 × 419.21
  4. Step 4: Simplify right side
    669.26x = 420,513.74
  5. Step 5: Solve for x
    x = 420,513.74/669.26
  6. Step 6: Final answer
    x = 628.33

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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.