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Finding the Fourth Proportional to 812.12, 1,217.90 and 264.17

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Solution

The fourth proportional to 812.12, 1,217.90 and 264.17 is: 396.17

Step by Step Solution

  1. Step 1: Write the proportion equation
    812.12 : 1,217.90 = 264.17 : x
  2. Step 2: Convert to fraction form
    812.12/1,217.90 = 264.17/x
  3. Step 3: Cross multiply
    812.12x = 1,217.90 × 264.17
  4. Step 4: Simplify right side
    812.12x = 321,736.35
  5. Step 5: Solve for x
    x = 321,736.35/812.12
  6. Step 6: Final answer
    x = 396.17

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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.