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Finding the Fourth Proportional to 639.90, 882.70 and 443.07

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Solution

The fourth proportional to 639.90, 882.70 and 443.07 is: 611.18

Step by Step Solution

  1. Step 1: Write the proportion equation
    639.90 : 882.70 = 443.07 : x
  2. Step 2: Convert to fraction form
    639.90/882.70 = 443.07/x
  3. Step 3: Cross multiply
    639.90x = 882.70 × 443.07
  4. Step 4: Simplify right side
    639.90x = 391,096.78
  5. Step 5: Solve for x
    x = 391,096.78/639.90
  6. Step 6: Final answer
    x = 611.18

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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.