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Finding the Fourth Proportional to 639.78, 882.93 and 419.32

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Solution

The fourth proportional to 639.78, 882.93 and 419.32 is: 578.68

Step by Step Solution

  1. Step 1: Write the proportion equation
    639.78 : 882.93 = 419.32 : x
  2. Step 2: Convert to fraction form
    639.78/882.93 = 419.32/x
  3. Step 3: Cross multiply
    639.78x = 882.93 × 419.32
  4. Step 4: Simplify right side
    639.78x = 370,230.21
  5. Step 5: Solve for x
    x = 370,230.21/639.78
  6. Step 6: Final answer
    x = 578.68

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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.