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Finding the Fourth Proportional to 640.78, 882.83 and 419.35

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Solution

The fourth proportional to 640.78, 882.83 and 419.35 is: 577.75

Step by Step Solution

  1. Step 1: Write the proportion equation
    640.78 : 882.83 = 419.35 : x
  2. Step 2: Convert to fraction form
    640.78/882.83 = 419.35/x
  3. Step 3: Cross multiply
    640.78x = 882.83 × 419.35
  4. Step 4: Simplify right side
    640.78x = 370,211.27
  5. Step 5: Solve for x
    x = 370,211.27/640.78
  6. Step 6: Final answer
    x = 577.75

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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.