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Finding the Fourth Proportional to 640.28, 883.62 and 419.82

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Solution

The fourth proportional to 640.28, 883.62 and 419.82 is: 579.37

Step by Step Solution

  1. Step 1: Write the proportion equation
    640.28 : 883.62 = 419.82 : x
  2. Step 2: Convert to fraction form
    640.28/883.62 = 419.82/x
  3. Step 3: Cross multiply
    640.28x = 883.62 × 419.82
  4. Step 4: Simplify right side
    640.28x = 370,961.35
  5. Step 5: Solve for x
    x = 370,961.35/640.28
  6. Step 6: Final answer
    x = 579.37

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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.