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Finding the Fourth Proportional to 681, 939.90 and 419.19

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Solution

The fourth proportional to 681, 939.90 and 419.19 is: 578.56

Step by Step Solution

  1. Step 1: Write the proportion equation
    681 : 939.90 = 419.19 : x
  2. Step 2: Convert to fraction form
    681/939.90 = 419.19/x
  3. Step 3: Cross multiply
    681x = 939.90 × 419.19
  4. Step 4: Simplify right side
    681x = 393,996.68
  5. Step 5: Solve for x
    x = 393,996.68/681
  6. Step 6: Final answer
    x = 578.56

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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.