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Finding the Fourth Proportional to 620.18, 855.28 and 479.85

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Solution

The fourth proportional to 620.18, 855.28 and 479.85 is: 661.75

Step by Step Solution

  1. Step 1: Write the proportion equation
    620.18 : 855.28 = 479.85 : x
  2. Step 2: Convert to fraction form
    620.18/855.28 = 479.85/x
  3. Step 3: Cross multiply
    620.18x = 855.28 × 479.85
  4. Step 4: Simplify right side
    620.18x = 410,406.71
  5. Step 5: Solve for x
    x = 410,406.71/620.18
  6. Step 6: Final answer
    x = 661.75

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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.