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Finding the Fourth Proportional to 620.20, 855.87 and 340.43

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Solution

The fourth proportional to 620.20, 855.87 and 340.43 is: 469.79

Step by Step Solution

  1. Step 1: Write the proportion equation
    620.20 : 855.87 = 340.43 : x
  2. Step 2: Convert to fraction form
    620.20/855.87 = 340.43/x
  3. Step 3: Cross multiply
    620.20x = 855.87 × 340.43
  4. Step 4: Simplify right side
    620.20x = 291,363.82
  5. Step 5: Solve for x
    x = 291,363.82/620.20
  6. Step 6: Final answer
    x = 469.79

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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.