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Finding the Fourth Proportional to 420.57, 630.79 and 225.96

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Solution

The fourth proportional to 420.57, 630.79 and 225.96 is: 338.91

Step by Step Solution

  1. Step 1: Write the proportion equation
    420.57 : 630.79 = 225.96 : x
  2. Step 2: Convert to fraction form
    420.57/630.79 = 225.96/x
  3. Step 3: Cross multiply
    420.57x = 630.79 × 225.96
  4. Step 4: Simplify right side
    420.57x = 142,533.31
  5. Step 5: Solve for x
    x = 142,533.31/420.57
  6. Step 6: Final answer
    x = 338.91

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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.