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Finding the Fourth Proportional to 287.13, 396.48 and 213.78

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Solution

The fourth proportional to 287.13, 396.48 and 213.78 is: 295.20

Step by Step Solution

  1. Step 1: Write the proportion equation
    287.13 : 396.48 = 213.78 : x
  2. Step 2: Convert to fraction form
    287.13/396.48 = 213.78/x
  3. Step 3: Cross multiply
    287.13x = 396.48 × 213.78
  4. Step 4: Simplify right side
    287.13x = 84,759.49
  5. Step 5: Solve for x
    x = 84,759.49/287.13
  6. Step 6: Final answer
    x = 295.20

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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.