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Finding the Fourth Proportional to 639.91, 883.44 and 419.09

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Solution

The fourth proportional to 639.91, 883.44 and 419.09 is: 578.57

Step by Step Solution

  1. Step 1: Write the proportion equation
    639.91 : 883.44 = 419.09 : x
  2. Step 2: Convert to fraction form
    639.91/883.44 = 419.09/x
  3. Step 3: Cross multiply
    639.91x = 883.44 × 419.09
  4. Step 4: Simplify right side
    639.91x = 370,234.36
  5. Step 5: Solve for x
    x = 370,234.36/639.91
  6. Step 6: Final answer
    x = 578.57

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.