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Finding the Fourth Proportional to 425.28, 637.79 and 219.91

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Solution

The fourth proportional to 425.28, 637.79 and 219.91 is: 329.80

Step by Step Solution

  1. Step 1: Write the proportion equation
    425.28 : 637.79 = 219.91 : x
  2. Step 2: Convert to fraction form
    425.28/637.79 = 219.91/x
  3. Step 3: Cross multiply
    425.28x = 637.79 × 219.91
  4. Step 4: Simplify right side
    425.28x = 140,256.40
  5. Step 5: Solve for x
    x = 140,256.40/425.28
  6. Step 6: Final answer
    x = 329.80

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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.