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Finding the Fourth Proportional to 681.61, 940.63 and 386.90

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Solution

The fourth proportional to 681.61, 940.63 and 386.90 is: 533.93

Step by Step Solution

  1. Step 1: Write the proportion equation
    681.61 : 940.63 = 386.90 : x
  2. Step 2: Convert to fraction form
    681.61/940.63 = 386.90/x
  3. Step 3: Cross multiply
    681.61x = 940.63 × 386.90
  4. Step 4: Simplify right side
    681.61x = 363,929.75
  5. Step 5: Solve for x
    x = 363,929.75/681.61
  6. Step 6: Final answer
    x = 533.93

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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.