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Finding the Fourth Proportional to 280.82, 387.78 and 231.62

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Solution

The fourth proportional to 280.82, 387.78 and 231.62 is: 319.84

Step by Step Solution

  1. Step 1: Write the proportion equation
    280.82 : 387.78 = 231.62 : x
  2. Step 2: Convert to fraction form
    280.82/387.78 = 231.62/x
  3. Step 3: Cross multiply
    280.82x = 387.78 × 231.62
  4. Step 4: Simplify right side
    280.82x = 89,817.60
  5. Step 5: Solve for x
    x = 89,817.60/280.82
  6. Step 6: Final answer
    x = 319.84

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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.