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Finding the Fourth Proportional to 866.31, 1,299.60 and 379.77

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Solution

The fourth proportional to 866.31, 1,299.60 and 379.77 is: 569.71

Step by Step Solution

  1. Step 1: Write the proportion equation
    866.31 : 1,299.60 = 379.77 : x
  2. Step 2: Convert to fraction form
    866.31/1,299.60 = 379.77/x
  3. Step 3: Cross multiply
    866.31x = 1,299.60 × 379.77
  4. Step 4: Simplify right side
    866.31x = 493,549.09
  5. Step 5: Solve for x
    x = 493,549.09/866.31
  6. Step 6: Final answer
    x = 569.71

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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.