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Finding the Fourth Proportional to 640.43, 884.28 and 419.30

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Solution

The fourth proportional to 640.43, 884.28 and 419.30 is: 578.95

Step by Step Solution

  1. Step 1: Write the proportion equation
    640.43 : 884.28 = 419.30 : x
  2. Step 2: Convert to fraction form
    640.43/884.28 = 419.30/x
  3. Step 3: Cross multiply
    640.43x = 884.28 × 419.30
  4. Step 4: Simplify right side
    640.43x = 370,778.60
  5. Step 5: Solve for x
    x = 370,778.60/640.43
  6. Step 6: Final answer
    x = 578.95

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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.