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Finding the Fourth Proportional to 872.62, 1,308.96 and 287.71

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Solution

The fourth proportional to 872.62, 1,308.96 and 287.71 is: 431.57

Step by Step Solution

  1. Step 1: Write the proportion equation
    872.62 : 1,308.96 = 287.71 : x
  2. Step 2: Convert to fraction form
    872.62/1,308.96 = 287.71/x
  3. Step 3: Cross multiply
    872.62x = 1,308.96 × 287.71
  4. Step 4: Simplify right side
    872.62x = 376,600.88
  5. Step 5: Solve for x
    x = 376,600.88/872.62
  6. Step 6: Final answer
    x = 431.57

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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.