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Finding the Fourth Proportional to 411.29, 620.24 and 405.80

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Solution

The fourth proportional to 411.29, 620.24 and 405.80 is: 611.96

Step by Step Solution

  1. Step 1: Write the proportion equation
    411.29 : 620.24 = 405.80 : x
  2. Step 2: Convert to fraction form
    411.29/620.24 = 405.80/x
  3. Step 3: Cross multiply
    411.29x = 620.24 × 405.80
  4. Step 4: Simplify right side
    411.29x = 251,693.39
  5. Step 5: Solve for x
    x = 251,693.39/411.29
  6. Step 6: Final answer
    x = 611.96

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Why These Related Problems?

These problems maintain the same ratio (1.51) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.