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Finding the Fourth Proportional to 812.09, 1,218.53 and 422.02

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Solution

The fourth proportional to 812.09, 1,218.53 and 422.02 is: 633.24

Step by Step Solution

  1. Step 1: Write the proportion equation
    812.09 : 1,218.53 = 422.02 : x
  2. Step 2: Convert to fraction form
    812.09/1,218.53 = 422.02/x
  3. Step 3: Cross multiply
    812.09x = 1,218.53 × 422.02
  4. Step 4: Simplify right side
    812.09x = 514,244.03
  5. Step 5: Solve for x
    x = 514,244.03/812.09
  6. Step 6: Final answer
    x = 633.24

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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.