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Finding the Fourth Proportional to 872.29, 1,200.31 and 805.20

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Solution

The fourth proportional to 872.29, 1,200.31 and 805.20 is: 1,107.99

Step by Step Solution

  1. Step 1: Write the proportion equation
    872.29 : 1,200.31 = 805.20 : x
  2. Step 2: Convert to fraction form
    872.29/1,200.31 = 805.20/x
  3. Step 3: Cross multiply
    872.29x = 1,200.31 × 805.20
  4. Step 4: Simplify right side
    872.29x = 966,489.61
  5. Step 5: Solve for x
    x = 966,489.61/872.29
  6. Step 6: Final answer
    x = 1,107.99

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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.