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Finding the Fourth Proportional to 431.31, 647.02 and 323.78

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Solution

The fourth proportional to 431.31, 647.02 and 323.78 is: 485.71

Step by Step Solution

  1. Step 1: Write the proportion equation
    431.31 : 647.02 = 323.78 : x
  2. Step 2: Convert to fraction form
    431.31/647.02 = 323.78/x
  3. Step 3: Cross multiply
    431.31x = 647.02 × 323.78
  4. Step 4: Simplify right side
    431.31x = 209,492.14
  5. Step 5: Solve for x
    x = 209,492.14/431.31
  6. Step 6: Final answer
    x = 485.71

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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.