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Finding the Fourth Proportional to 685.09, 945.60 and 422.95

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Solution

The fourth proportional to 685.09, 945.60 and 422.95 is: 583.79

Step by Step Solution

  1. Step 1: Write the proportion equation
    685.09 : 945.60 = 422.95 : x
  2. Step 2: Convert to fraction form
    685.09/945.60 = 422.95/x
  3. Step 3: Cross multiply
    685.09x = 945.60 × 422.95
  4. Step 4: Simplify right side
    685.09x = 399,945.27
  5. Step 5: Solve for x
    x = 399,945.27/685.09
  6. Step 6: Final answer
    x = 583.79

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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.