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Finding the Fourth Proportional to 287.79, 396.87 and 208.97

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Solution

The fourth proportional to 287.79, 396.87 and 208.97 is: 288.18

Step by Step Solution

  1. Step 1: Write the proportion equation
    287.79 : 396.87 = 208.97 : x
  2. Step 2: Convert to fraction form
    287.79/396.87 = 208.97/x
  3. Step 3: Cross multiply
    287.79x = 396.87 × 208.97
  4. Step 4: Simplify right side
    287.79x = 82,933.92
  5. Step 5: Solve for x
    x = 82,933.92/287.79
  6. Step 6: Final answer
    x = 288.18

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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.