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Finding the Fourth Proportional to 805.18, 1,207.57 and 311.42

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Solution

The fourth proportional to 805.18, 1,207.57 and 311.42 is: 467.05

Step by Step Solution

  1. Step 1: Write the proportion equation
    805.18 : 1,207.57 = 311.42 : x
  2. Step 2: Convert to fraction form
    805.18/1,207.57 = 311.42/x
  3. Step 3: Cross multiply
    805.18x = 1,207.57 × 311.42
  4. Step 4: Simplify right side
    805.18x = 376,059.89
  5. Step 5: Solve for x
    x = 376,059.89/805.18
  6. Step 6: Final answer
    x = 467.05

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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.