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Finding the Fourth Proportional to 620.19, 855.90 and 354.65

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Solution

The fourth proportional to 620.19, 855.90 and 354.65 is: 489.43

Step by Step Solution

  1. Step 1: Write the proportion equation
    620.19 : 855.90 = 354.65 : x
  2. Step 2: Convert to fraction form
    620.19/855.90 = 354.65/x
  3. Step 3: Cross multiply
    620.19x = 855.90 × 354.65
  4. Step 4: Simplify right side
    620.19x = 303,540.66
  5. Step 5: Solve for x
    x = 303,540.66/620.19
  6. Step 6: Final answer
    x = 489.43

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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.