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Finding the Fourth Proportional to 420.86, 631.21 and 225.25

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Solution

The fourth proportional to 420.86, 631.21 and 225.25 is: 337.83

Step by Step Solution

  1. Step 1: Write the proportion equation
    420.86 : 631.21 = 225.25 : x
  2. Step 2: Convert to fraction form
    420.86/631.21 = 225.25/x
  3. Step 3: Cross multiply
    420.86x = 631.21 × 225.25
  4. Step 4: Simplify right side
    420.86x = 142,180.05
  5. Step 5: Solve for x
    x = 142,180.05/420.86
  6. Step 6: Final answer
    x = 337.83

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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.