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Finding the Fourth Proportional to 639.86, 883.41 and 443.30

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Solution

The fourth proportional to 639.86, 883.41 and 443.30 is: 612.03

Step by Step Solution

  1. Step 1: Write the proportion equation
    639.86 : 883.41 = 443.30 : x
  2. Step 2: Convert to fraction form
    639.86/883.41 = 443.30/x
  3. Step 3: Cross multiply
    639.86x = 883.41 × 443.30
  4. Step 4: Simplify right side
    639.86x = 391,615.65
  5. Step 5: Solve for x
    x = 391,615.65/639.86
  6. Step 6: Final answer
    x = 612.03

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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.