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Finding the Fourth Proportional to 721.10, 1,081.18 and 310.12

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Solution

The fourth proportional to 721.10, 1,081.18 and 310.12 is: 464.98

Step by Step Solution

  1. Step 1: Write the proportion equation
    721.10 : 1,081.18 = 310.12 : x
  2. Step 2: Convert to fraction form
    721.10/1,081.18 = 310.12/x
  3. Step 3: Cross multiply
    721.10x = 1,081.18 × 310.12
  4. Step 4: Simplify right side
    721.10x = 335,295.54
  5. Step 5: Solve for x
    x = 335,295.54/721.10
  6. Step 6: Final answer
    x = 464.98

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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.