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Finding the Fourth Proportional to 639.09, 882.90 and 509.49

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Solution

The fourth proportional to 639.09, 882.90 and 509.49 is: 703.86

Step by Step Solution

  1. Step 1: Write the proportion equation
    639.09 : 882.90 = 509.49 : x
  2. Step 2: Convert to fraction form
    639.09/882.90 = 509.49/x
  3. Step 3: Cross multiply
    639.09x = 882.90 × 509.49
  4. Step 4: Simplify right side
    639.09x = 449,828.72
  5. Step 5: Solve for x
    x = 449,828.72/639.09
  6. Step 6: Final answer
    x = 703.86

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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.