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Finding the Fourth Proportional to 381.25, 571.85 and 198.75

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Solution

The fourth proportional to 381.25, 571.85 and 198.75 is: 298.11

Step by Step Solution

  1. Step 1: Write the proportion equation
    381.25 : 571.85 = 198.75 : x
  2. Step 2: Convert to fraction form
    381.25/571.85 = 198.75/x
  3. Step 3: Cross multiply
    381.25x = 571.85 × 198.75
  4. Step 4: Simplify right side
    381.25x = 113,655.19
  5. Step 5: Solve for x
    x = 113,655.19/381.25
  6. Step 6: Final answer
    x = 298.11

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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.