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Finding the Fourth Proportional to 208.31, 311.08 and 197.78

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Solution

The fourth proportional to 208.31, 311.08 and 197.78 is: 295.36

Step by Step Solution

  1. Step 1: Write the proportion equation
    208.31 : 311.08 = 197.78 : x
  2. Step 2: Convert to fraction form
    208.31/311.08 = 197.78/x
  3. Step 3: Cross multiply
    208.31x = 311.08 × 197.78
  4. Step 4: Simplify right side
    208.31x = 61,525.40
  5. Step 5: Solve for x
    x = 61,525.40/208.31
  6. Step 6: Final answer
    x = 295.36

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.