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Finding the Fourth Proportional to 681.59, 940.65 and 386.87

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Solution

The fourth proportional to 681.59, 940.65 and 386.87 is: 533.91

Step by Step Solution

  1. Step 1: Write the proportion equation
    681.59 : 940.65 = 386.87 : x
  2. Step 2: Convert to fraction form
    681.59/940.65 = 386.87/x
  3. Step 3: Cross multiply
    681.59x = 940.65 × 386.87
  4. Step 4: Simplify right side
    681.59x = 363,909.27
  5. Step 5: Solve for x
    x = 363,909.27/681.59
  6. Step 6: Final answer
    x = 533.91

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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.