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Finding the Fourth Proportional to 812.87, 1,121.78 and 458.86

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Solution

The fourth proportional to 812.87, 1,121.78 and 458.86 is: 633.24

Step by Step Solution

  1. Step 1: Write the proportion equation
    812.87 : 1,121.78 = 458.86 : x
  2. Step 2: Convert to fraction form
    812.87/1,121.78 = 458.86/x
  3. Step 3: Cross multiply
    812.87x = 1,121.78 × 458.86
  4. Step 4: Simplify right side
    812.87x = 514,740.48
  5. Step 5: Solve for x
    x = 514,740.48/812.87
  6. Step 6: Final answer
    x = 633.24

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.