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Finding the Fourth Proportional to 803.31, 1,109.87 and 638.88

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Solution

The fourth proportional to 803.31, 1,109.87 and 638.88 is: 882.69

Step by Step Solution

  1. Step 1: Write the proportion equation
    803.31 : 1,109.87 = 638.88 : x
  2. Step 2: Convert to fraction form
    803.31/1,109.87 = 638.88/x
  3. Step 3: Cross multiply
    803.31x = 1,109.87 × 638.88
  4. Step 4: Simplify right side
    803.31x = 709,073.75
  5. Step 5: Solve for x
    x = 709,073.75/803.31
  6. Step 6: Final answer
    x = 882.69

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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.