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Finding the Fourth Proportional to 681.85, 940.95 and 387.11

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Solution

The fourth proportional to 681.85, 940.95 and 387.11 is: 534.21

Step by Step Solution

  1. Step 1: Write the proportion equation
    681.85 : 940.95 = 387.11 : x
  2. Step 2: Convert to fraction form
    681.85/940.95 = 387.11/x
  3. Step 3: Cross multiply
    681.85x = 940.95 × 387.11
  4. Step 4: Simplify right side
    681.85x = 364,251.15
  5. Step 5: Solve for x
    x = 364,251.15/681.85
  6. Step 6: Final answer
    x = 534.21

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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.