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Finding the Fourth Proportional to 638.80, 881.96 and 403.08

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Solution

The fourth proportional to 638.80, 881.96 and 403.08 is: 556.51

Step by Step Solution

  1. Step 1: Write the proportion equation
    638.80 : 881.96 = 403.08 : x
  2. Step 2: Convert to fraction form
    638.80/881.96 = 403.08/x
  3. Step 3: Cross multiply
    638.80x = 881.96 × 403.08
  4. Step 4: Simplify right side
    638.80x = 355,500.44
  5. Step 5: Solve for x
    x = 355,500.44/638.80
  6. Step 6: Final answer
    x = 556.51

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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.