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Finding the Fourth Proportional to 660.27, 989.48 and 640.56

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Solution

The fourth proportional to 660.27, 989.48 and 640.56 is: 959.94

Step by Step Solution

  1. Step 1: Write the proportion equation
    660.27 : 989.48 = 640.56 : x
  2. Step 2: Convert to fraction form
    660.27/989.48 = 640.56/x
  3. Step 3: Cross multiply
    660.27x = 989.48 × 640.56
  4. Step 4: Simplify right side
    660.27x = 633,816.36
  5. Step 5: Solve for x
    x = 633,816.36/660.27
  6. Step 6: Final answer
    x = 959.94

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.