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Finding the Fourth Proportional to 681.06, 939.64 and 401.20

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Solution

The fourth proportional to 681.06, 939.64 and 401.20 is: 553.52

Step by Step Solution

  1. Step 1: Write the proportion equation
    681.06 : 939.64 = 401.20 : x
  2. Step 2: Convert to fraction form
    681.06/939.64 = 401.20/x
  3. Step 3: Cross multiply
    681.06x = 939.64 × 401.20
  4. Step 4: Simplify right side
    681.06x = 376,983.57
  5. Step 5: Solve for x
    x = 376,983.57/681.06
  6. Step 6: Final answer
    x = 553.52

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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.