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Finding the Fourth Proportional to 287.35, 396.70 and 216.85

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Solution

The fourth proportional to 287.35, 396.70 and 216.85 is: 299.37

Step by Step Solution

  1. Step 1: Write the proportion equation
    287.35 : 396.70 = 216.85 : x
  2. Step 2: Convert to fraction form
    287.35/396.70 = 216.85/x
  3. Step 3: Cross multiply
    287.35x = 396.70 × 216.85
  4. Step 4: Simplify right side
    287.35x = 86,025.93
  5. Step 5: Solve for x
    x = 86,025.93/287.35
  6. Step 6: Final answer
    x = 299.37

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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.