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Finding the Fourth Proportional to 638.56, 959.69 and 423.51

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Solution

The fourth proportional to 638.56, 959.69 and 423.51 is: 636.49

Step by Step Solution

  1. Step 1: Write the proportion equation
    638.56 : 959.69 = 423.51 : x
  2. Step 2: Convert to fraction form
    638.56/959.69 = 423.51/x
  3. Step 3: Cross multiply
    638.56x = 959.69 × 423.51
  4. Step 4: Simplify right side
    638.56x = 406,438.31
  5. Step 5: Solve for x
    x = 406,438.31/638.56
  6. Step 6: Final answer
    x = 636.49

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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.