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Finding the Fourth Proportional to 380.90, 571.15 and 198.25

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Solution

The fourth proportional to 380.90, 571.15 and 198.25 is: 297.27

Step by Step Solution

  1. Step 1: Write the proportion equation
    380.90 : 571.15 = 198.25 : x
  2. Step 2: Convert to fraction form
    380.90/571.15 = 198.25/x
  3. Step 3: Cross multiply
    380.90x = 571.15 × 198.25
  4. Step 4: Simplify right side
    380.90x = 113,229.31
  5. Step 5: Solve for x
    x = 113,229.31/380.90
  6. Step 6: Final answer
    x = 297.27

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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.