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Finding the Fourth Proportional to 660.38, 990.42 and 198.10

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Solution

The fourth proportional to 660.38, 990.42 and 198.10 is: 297.10

Step by Step Solution

  1. Step 1: Write the proportion equation
    660.38 : 990.42 = 198.10 : x
  2. Step 2: Convert to fraction form
    660.38/990.42 = 198.10/x
  3. Step 3: Cross multiply
    660.38x = 990.42 × 198.10
  4. Step 4: Simplify right side
    660.38x = 196,196.26
  5. Step 5: Solve for x
    x = 196,196.26/660.38
  6. Step 6: Final answer
    x = 297.10

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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.