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Finding the Fourth Proportional to 217.66, 326.85 and 208.30

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Solution

The fourth proportional to 217.66, 326.85 and 208.30 is: 312.79

Step by Step Solution

  1. Step 1: Write the proportion equation
    217.66 : 326.85 = 208.30 : x
  2. Step 2: Convert to fraction form
    217.66/326.85 = 208.30/x
  3. Step 3: Cross multiply
    217.66x = 326.85 × 208.30
  4. Step 4: Simplify right side
    217.66x = 68,080.18
  5. Step 5: Solve for x
    x = 68,080.18/217.66
  6. Step 6: Final answer
    x = 312.79

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.