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Finding the Fourth Proportional to 486.41, 727.52 and 420.80

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Solution

The fourth proportional to 486.41, 727.52 and 420.80 is: 629.38

Step by Step Solution

  1. Step 1: Write the proportion equation
    486.41 : 727.52 = 420.80 : x
  2. Step 2: Convert to fraction form
    486.41/727.52 = 420.80/x
  3. Step 3: Cross multiply
    486.41x = 727.52 × 420.80
  4. Step 4: Simplify right side
    486.41x = 306,134.67
  5. Step 5: Solve for x
    x = 306,134.67/486.41
  6. Step 6: Final answer
    x = 629.38

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.