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Finding the Fourth Proportional to 399.29, 598.31 and 308.21

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Solution

The fourth proportional to 399.29, 598.31 and 308.21 is: 461.83

Step by Step Solution

  1. Step 1: Write the proportion equation
    399.29 : 598.31 = 308.21 : x
  2. Step 2: Convert to fraction form
    399.29/598.31 = 308.21/x
  3. Step 3: Cross multiply
    399.29x = 598.31 × 308.21
  4. Step 4: Simplify right side
    399.29x = 184,405.08
  5. Step 5: Solve for x
    x = 184,405.08/399.29
  6. Step 6: Final answer
    x = 461.83

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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.