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Finding the Fourth Proportional to 420.23, 629.96 and 255.29

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Solution

The fourth proportional to 420.23, 629.96 and 255.29 is: 382.70

Step by Step Solution

  1. Step 1: Write the proportion equation
    420.23 : 629.96 = 255.29 : x
  2. Step 2: Convert to fraction form
    420.23/629.96 = 255.29/x
  3. Step 3: Cross multiply
    420.23x = 629.96 × 255.29
  4. Step 4: Simplify right side
    420.23x = 160,822.79
  5. Step 5: Solve for x
    x = 160,822.79/420.23
  6. Step 6: Final answer
    x = 382.70

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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.