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Finding the Fourth Proportional to 620.82, 856.71 and 351.61

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Solution

The fourth proportional to 620.82, 856.71 and 351.61 is: 485.21

Step by Step Solution

  1. Step 1: Write the proportion equation
    620.82 : 856.71 = 351.61 : x
  2. Step 2: Convert to fraction form
    620.82/856.71 = 351.61/x
  3. Step 3: Cross multiply
    620.82x = 856.71 × 351.61
  4. Step 4: Simplify right side
    620.82x = 301,227.80
  5. Step 5: Solve for x
    x = 301,227.80/620.82
  6. Step 6: Final answer
    x = 485.21

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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.