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Finding the Fourth Proportional to 660.60, 996.21 and 656.28

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Solution

The fourth proportional to 660.60, 996.21 and 656.28 is: 989.70

Step by Step Solution

  1. Step 1: Write the proportion equation
    660.60 : 996.21 = 656.28 : x
  2. Step 2: Convert to fraction form
    660.60/996.21 = 656.28/x
  3. Step 3: Cross multiply
    660.60x = 996.21 × 656.28
  4. Step 4: Simplify right side
    660.60x = 653,792.70
  5. Step 5: Solve for x
    x = 653,792.70/660.60
  6. Step 6: Final answer
    x = 989.70

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Why These Related Problems?

These problems maintain the same ratio (1.51) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.