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Finding the Fourth Proportional to 721.05, 1,081.62 and 310.19

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Solution

The fourth proportional to 721.05, 1,081.62 and 310.19 is: 465.30

Step by Step Solution

  1. Step 1: Write the proportion equation
    721.05 : 1,081.62 = 310.19 : x
  2. Step 2: Convert to fraction form
    721.05/1,081.62 = 310.19/x
  3. Step 3: Cross multiply
    721.05x = 1,081.62 × 310.19
  4. Step 4: Simplify right side
    721.05x = 335,502.30
  5. Step 5: Solve for x
    x = 335,502.30/721.05
  6. Step 6: Final answer
    x = 465.30

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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.