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Finding the Fourth Proportional to 638.30, 958.26 and 407.46

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Solution

The fourth proportional to 638.30, 958.26 and 407.46 is: 611.71

Step by Step Solution

  1. Step 1: Write the proportion equation
    638.30 : 958.26 = 407.46 : x
  2. Step 2: Convert to fraction form
    638.30/958.26 = 407.46/x
  3. Step 3: Cross multiply
    638.30x = 958.26 × 407.46
  4. Step 4: Simplify right side
    638.30x = 390,452.62
  5. Step 5: Solve for x
    x = 390,452.62/638.30
  6. Step 6: Final answer
    x = 611.71

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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.