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Finding the Fourth Proportional to 681.86, 940.95 and 387.20

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Solution

The fourth proportional to 681.86, 940.95 and 387.20 is: 534.32

Step by Step Solution

  1. Step 1: Write the proportion equation
    681.86 : 940.95 = 387.20 : x
  2. Step 2: Convert to fraction form
    681.86/940.95 = 387.20/x
  3. Step 3: Cross multiply
    681.86x = 940.95 × 387.20
  4. Step 4: Simplify right side
    681.86x = 364,331.14
  5. Step 5: Solve for x
    x = 364,331.14/681.86
  6. Step 6: Final answer
    x = 534.32

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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.