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Finding the Fourth Proportional to 414.05, 620.40 and 345.20

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Solution

The fourth proportional to 414.05, 620.40 and 345.20 is: 517.24

Step by Step Solution

  1. Step 1: Write the proportion equation
    414.05 : 620.40 = 345.20 : x
  2. Step 2: Convert to fraction form
    414.05/620.40 = 345.20/x
  3. Step 3: Cross multiply
    414.05x = 620.40 × 345.20
  4. Step 4: Simplify right side
    414.05x = 214,162.08
  5. Step 5: Solve for x
    x = 214,162.08/414.05
  6. Step 6: Final answer
    x = 517.24

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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.