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Finding the Fourth Proportional to 638.31, 880.76 and 401.84

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Solution

The fourth proportional to 638.31, 880.76 and 401.84 is: 554.47

Step by Step Solution

  1. Step 1: Write the proportion equation
    638.31 : 880.76 = 401.84 : x
  2. Step 2: Convert to fraction form
    638.31/880.76 = 401.84/x
  3. Step 3: Cross multiply
    638.31x = 880.76 × 401.84
  4. Step 4: Simplify right side
    638.31x = 353,922.59
  5. Step 5: Solve for x
    x = 353,922.59/638.31
  6. Step 6: Final answer
    x = 554.47

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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.