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Finding the Fourth Proportional to 638.22, 880.71 and 402.12

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Solution

The fourth proportional to 638.22, 880.71 and 402.12 is: 554.90

Step by Step Solution

  1. Step 1: Write the proportion equation
    638.22 : 880.71 = 402.12 : x
  2. Step 2: Convert to fraction form
    638.22/880.71 = 402.12/x
  3. Step 3: Cross multiply
    638.22x = 880.71 × 402.12
  4. Step 4: Simplify right side
    638.22x = 354,151.11
  5. Step 5: Solve for x
    x = 354,151.11/638.22
  6. Step 6: Final answer
    x = 554.90

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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.