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Finding the Fourth Proportional to 287.32, 396.29 and 217.39

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Solution

The fourth proportional to 287.32, 396.29 and 217.39 is: 299.84

Step by Step Solution

  1. Step 1: Write the proportion equation
    287.32 : 396.29 = 217.39 : x
  2. Step 2: Convert to fraction form
    287.32/396.29 = 217.39/x
  3. Step 3: Cross multiply
    287.32x = 396.29 × 217.39
  4. Step 4: Simplify right side
    287.32x = 86,149.48
  5. Step 5: Solve for x
    x = 86,149.48/287.32
  6. Step 6: Final answer
    x = 299.84

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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.