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Finding the Fourth Proportional to 681.35, 940.20 and 386.61

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Solution

The fourth proportional to 681.35, 940.20 and 386.61 is: 533.49

Step by Step Solution

  1. Step 1: Write the proportion equation
    681.35 : 940.20 = 386.61 : x
  2. Step 2: Convert to fraction form
    681.35/940.20 = 386.61/x
  3. Step 3: Cross multiply
    681.35x = 940.20 × 386.61
  4. Step 4: Simplify right side
    681.35x = 363,490.72
  5. Step 5: Solve for x
    x = 363,490.72/681.35
  6. Step 6: Final answer
    x = 533.49

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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.