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Finding the Fourth Proportional to 805.17, 1,207.89 and 394.05

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Solution

The fourth proportional to 805.17, 1,207.89 and 394.05 is: 591.14

Step by Step Solution

  1. Step 1: Write the proportion equation
    805.17 : 1,207.89 = 394.05 : x
  2. Step 2: Convert to fraction form
    805.17/1,207.89 = 394.05/x
  3. Step 3: Cross multiply
    805.17x = 1,207.89 × 394.05
  4. Step 4: Simplify right side
    805.17x = 475,969.05
  5. Step 5: Solve for x
    x = 475,969.05/805.17
  6. Step 6: Final answer
    x = 591.14

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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.