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Finding the Fourth Proportional to 425.99, 639.07 and 220.51

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Solution

The fourth proportional to 425.99, 639.07 and 220.51 is: 330.80

Step by Step Solution

  1. Step 1: Write the proportion equation
    425.99 : 639.07 = 220.51 : x
  2. Step 2: Convert to fraction form
    425.99/639.07 = 220.51/x
  3. Step 3: Cross multiply
    425.99x = 639.07 × 220.51
  4. Step 4: Simplify right side
    425.99x = 140,919.22
  5. Step 5: Solve for x
    x = 140,919.22/425.99
  6. Step 6: Final answer
    x = 330.80

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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.