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Finding the Fourth Proportional to 660.79, 991.32 and 198.57

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Solution

The fourth proportional to 660.79, 991.32 and 198.57 is: 297.89

Step by Step Solution

  1. Step 1: Write the proportion equation
    660.79 : 991.32 = 198.57 : x
  2. Step 2: Convert to fraction form
    660.79/991.32 = 198.57/x
  3. Step 3: Cross multiply
    660.79x = 991.32 × 198.57
  4. Step 4: Simplify right side
    660.79x = 196,844.93
  5. Step 5: Solve for x
    x = 196,844.93/660.79
  6. Step 6: Final answer
    x = 297.89

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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.