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Finding the Fourth Proportional to 512.10, 764.21 and 408.90

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Solution

The fourth proportional to 512.10, 764.21 and 408.90 is: 610.20

Step by Step Solution

  1. Step 1: Write the proportion equation
    512.10 : 764.21 = 408.90 : x
  2. Step 2: Convert to fraction form
    512.10/764.21 = 408.90/x
  3. Step 3: Cross multiply
    512.10x = 764.21 × 408.90
  4. Step 4: Simplify right side
    512.10x = 312,483.42
  5. Step 5: Solve for x
    x = 312,483.42/512.10
  6. Step 6: Final answer
    x = 610.20

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.