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Finding the Fourth Proportional to 811.29, 1,216.89 and 324

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Solution

The fourth proportional to 811.29, 1,216.89 and 324 is: 485.98

Step by Step Solution

  1. Step 1: Write the proportion equation
    811.29 : 1,216.89 = 324 : x
  2. Step 2: Convert to fraction form
    811.29/1,216.89 = 324/x
  3. Step 3: Cross multiply
    811.29x = 1,216.89 × 324
  4. Step 4: Simplify right side
    811.29x = 394,272.36
  5. Step 5: Solve for x
    x = 394,272.36/811.29
  6. Step 6: Final answer
    x = 485.98

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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.