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Finding the Fourth Proportional to 811.52, 1,218 and 427.04

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Solution

The fourth proportional to 811.52, 1,218 and 427.04 is: 640.94

Step by Step Solution

  1. Step 1: Write the proportion equation
    811.52 : 1,218 = 427.04 : x
  2. Step 2: Convert to fraction form
    811.52/1,218 = 427.04/x
  3. Step 3: Cross multiply
    811.52x = 1,218 × 427.04
  4. Step 4: Simplify right side
    811.52x = 520,134.72
  5. Step 5: Solve for x
    x = 520,134.72/811.52
  6. Step 6: Final answer
    x = 640.94

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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.