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Finding the Fourth Proportional to 420.57, 630.92 and 225.70

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Solution

The fourth proportional to 420.57, 630.92 and 225.70 is: 338.58

Step by Step Solution

  1. Step 1: Write the proportion equation
    420.57 : 630.92 = 225.70 : x
  2. Step 2: Convert to fraction form
    420.57/630.92 = 225.70/x
  3. Step 3: Cross multiply
    420.57x = 630.92 × 225.70
  4. Step 4: Simplify right side
    420.57x = 142,397.63
  5. Step 5: Solve for x
    x = 142,397.63/420.57
  6. Step 6: Final answer
    x = 338.58

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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.