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Finding the Fourth Proportional to 218.32, 299.96 and 208.78

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Solution

The fourth proportional to 218.32, 299.96 and 208.78 is: 286.85

Step by Step Solution

  1. Step 1: Write the proportion equation
    218.32 : 299.96 = 208.78 : x
  2. Step 2: Convert to fraction form
    218.32/299.96 = 208.78/x
  3. Step 3: Cross multiply
    218.32x = 299.96 × 208.78
  4. Step 4: Simplify right side
    218.32x = 62,625.65
  5. Step 5: Solve for x
    x = 62,625.65/218.32
  6. Step 6: Final answer
    x = 286.85

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Why These Related Problems?

These problems maintain the same ratio (1.37) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.