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Finding the Fourth Proportional to 620.39, 855.15 and 423.56

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Solution

The fourth proportional to 620.39, 855.15 and 423.56 is: 583.84

Step by Step Solution

  1. Step 1: Write the proportion equation
    620.39 : 855.15 = 423.56 : x
  2. Step 2: Convert to fraction form
    620.39/855.15 = 423.56/x
  3. Step 3: Cross multiply
    620.39x = 855.15 × 423.56
  4. Step 4: Simplify right side
    620.39x = 362,207.33
  5. Step 5: Solve for x
    x = 362,207.33/620.39
  6. Step 6: Final answer
    x = 583.84

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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.