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Finding the Fourth Proportional to 450.39, 620.30 and 421.11

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Solution

The fourth proportional to 450.39, 620.30 and 421.11 is: 579.97

Step by Step Solution

  1. Step 1: Write the proportion equation
    450.39 : 620.30 = 421.11 : x
  2. Step 2: Convert to fraction form
    450.39/620.30 = 421.11/x
  3. Step 3: Cross multiply
    450.39x = 620.30 × 421.11
  4. Step 4: Simplify right side
    450.39x = 261,212.43
  5. Step 5: Solve for x
    x = 261,212.43/450.39
  6. Step 6: Final answer
    x = 579.97

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.