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Finding the Fourth Proportional to 638.48, 881.09 and 354.88

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Solution

The fourth proportional to 638.48, 881.09 and 354.88 is: 489.72

Step by Step Solution

  1. Step 1: Write the proportion equation
    638.48 : 881.09 = 354.88 : x
  2. Step 2: Convert to fraction form
    638.48/881.09 = 354.88/x
  3. Step 3: Cross multiply
    638.48x = 881.09 × 354.88
  4. Step 4: Simplify right side
    638.48x = 312,677.24
  5. Step 5: Solve for x
    x = 312,677.24/638.48
  6. Step 6: Final answer
    x = 489.72

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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.