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Finding the Fourth Proportional to 681.76, 939.80 and 419.32

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Solution

The fourth proportional to 681.76, 939.80 and 419.32 is: 578.03

Step by Step Solution

  1. Step 1: Write the proportion equation
    681.76 : 939.80 = 419.32 : x
  2. Step 2: Convert to fraction form
    681.76/939.80 = 419.32/x
  3. Step 3: Cross multiply
    681.76x = 939.80 × 419.32
  4. Step 4: Simplify right side
    681.76x = 394,076.94
  5. Step 5: Solve for x
    x = 394,076.94/681.76
  6. Step 6: Final answer
    x = 578.03

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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.