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Finding the Fourth Proportional to 685.27, 945.80 and 401.85

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Solution

The fourth proportional to 685.27, 945.80 and 401.85 is: 554.63

Step by Step Solution

  1. Step 1: Write the proportion equation
    685.27 : 945.80 = 401.85 : x
  2. Step 2: Convert to fraction form
    685.27/945.80 = 401.85/x
  3. Step 3: Cross multiply
    685.27x = 945.80 × 401.85
  4. Step 4: Simplify right side
    685.27x = 380,069.73
  5. Step 5: Solve for x
    x = 380,069.73/685.27
  6. Step 6: Final answer
    x = 554.63

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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.