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Finding the Fourth Proportional to 813.05, 1,219.31 and 265.11

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Solution

The fourth proportional to 813.05, 1,219.31 and 265.11 is: 397.58

Step by Step Solution

  1. Step 1: Write the proportion equation
    813.05 : 1,219.31 = 265.11 : x
  2. Step 2: Convert to fraction form
    813.05/1,219.31 = 265.11/x
  3. Step 3: Cross multiply
    813.05x = 1,219.31 × 265.11
  4. Step 4: Simplify right side
    813.05x = 323,249.95
  5. Step 5: Solve for x
    x = 323,249.95/813.05
  6. Step 6: Final answer
    x = 397.58

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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.