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Finding the Fourth Proportional to 812.05, 1,217.79 and 291.89

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Solution

The fourth proportional to 812.05, 1,217.79 and 291.89 is: 437.74

Step by Step Solution

  1. Step 1: Write the proportion equation
    812.05 : 1,217.79 = 291.89 : x
  2. Step 2: Convert to fraction form
    812.05/1,217.79 = 291.89/x
  3. Step 3: Cross multiply
    812.05x = 1,217.79 × 291.89
  4. Step 4: Simplify right side
    812.05x = 355,463.77
  5. Step 5: Solve for x
    x = 355,463.77/812.05
  6. Step 6: Final answer
    x = 437.74

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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.