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Finding the Fourth Proportional to 620.10, 855.78 and 354.62

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Solution

The fourth proportional to 620.10, 855.78 and 354.62 is: 489.40

Step by Step Solution

  1. Step 1: Write the proportion equation
    620.10 : 855.78 = 354.62 : x
  2. Step 2: Convert to fraction form
    620.10/855.78 = 354.62/x
  3. Step 3: Cross multiply
    620.10x = 855.78 × 354.62
  4. Step 4: Simplify right side
    620.10x = 303,476.70
  5. Step 5: Solve for x
    x = 303,476.70/620.10
  6. Step 6: Final answer
    x = 489.40

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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.