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Finding the Fourth Proportional to 638.45, 880.72 and 376.31

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Solution

The fourth proportional to 638.45, 880.72 and 376.31 is: 519.11

Step by Step Solution

  1. Step 1: Write the proportion equation
    638.45 : 880.72 = 376.31 : x
  2. Step 2: Convert to fraction form
    638.45/880.72 = 376.31/x
  3. Step 3: Cross multiply
    638.45x = 880.72 × 376.31
  4. Step 4: Simplify right side
    638.45x = 331,427.12
  5. Step 5: Solve for x
    x = 331,427.12/638.45
  6. Step 6: Final answer
    x = 519.11

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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.