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Finding the Fourth Proportional to 638.50, 881.15 and 376.51

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Solution

The fourth proportional to 638.50, 881.15 and 376.51 is: 519.60

Step by Step Solution

  1. Step 1: Write the proportion equation
    638.50 : 881.15 = 376.51 : x
  2. Step 2: Convert to fraction form
    638.50/881.15 = 376.51/x
  3. Step 3: Cross multiply
    638.50x = 881.15 × 376.51
  4. Step 4: Simplify right side
    638.50x = 331,761.79
  5. Step 5: Solve for x
    x = 331,761.79/638.50
  6. Step 6: Final answer
    x = 519.60

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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.