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Finding the Fourth Proportional to 638.80, 881.64 and 376.84

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Solution

The fourth proportional to 638.80, 881.64 and 376.84 is: 520.10

Step by Step Solution

  1. Step 1: Write the proportion equation
    638.80 : 881.64 = 376.84 : x
  2. Step 2: Convert to fraction form
    638.80/881.64 = 376.84/x
  3. Step 3: Cross multiply
    638.80x = 881.64 × 376.84
  4. Step 4: Simplify right side
    638.80x = 332,237.22
  5. Step 5: Solve for x
    x = 332,237.22/638.80
  6. Step 6: Final answer
    x = 520.10

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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.