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Finding the Fourth Proportional to 280.85, 387.72 and 196.95

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Solution

The fourth proportional to 280.85, 387.72 and 196.95 is: 271.90

Step by Step Solution

  1. Step 1: Write the proportion equation
    280.85 : 387.72 = 196.95 : x
  2. Step 2: Convert to fraction form
    280.85/387.72 = 196.95/x
  3. Step 3: Cross multiply
    280.85x = 387.72 × 196.95
  4. Step 4: Simplify right side
    280.85x = 76,361.45
  5. Step 5: Solve for x
    x = 76,361.45/280.85
  6. Step 6: Final answer
    x = 271.90

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.