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Finding the Fourth Proportional to 681.46, 940.42 and 386.78

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Solution

The fourth proportional to 681.46, 940.42 and 386.78 is: 533.76

Step by Step Solution

  1. Step 1: Write the proportion equation
    681.46 : 940.42 = 386.78 : x
  2. Step 2: Convert to fraction form
    681.46/940.42 = 386.78/x
  3. Step 3: Cross multiply
    681.46x = 940.42 × 386.78
  4. Step 4: Simplify right side
    681.46x = 363,735.65
  5. Step 5: Solve for x
    x = 363,735.65/681.46
  6. Step 6: Final answer
    x = 533.76

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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.