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Finding the Fourth Proportional to 660.03, 990.20 and 197.80

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Solution

The fourth proportional to 660.03, 990.20 and 197.80 is: 296.75

Step by Step Solution

  1. Step 1: Write the proportion equation
    660.03 : 990.20 = 197.80 : x
  2. Step 2: Convert to fraction form
    660.03/990.20 = 197.80/x
  3. Step 3: Cross multiply
    660.03x = 990.20 × 197.80
  4. Step 4: Simplify right side
    660.03x = 195,861.56
  5. Step 5: Solve for x
    x = 195,861.56/660.03
  6. Step 6: Final answer
    x = 296.75

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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.