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Finding the Fourth Proportional to 638.38, 956.91 and 419.18

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Solution

The fourth proportional to 638.38, 956.91 and 419.18 is: 628.33

Step by Step Solution

  1. Step 1: Write the proportion equation
    638.38 : 956.91 = 419.18 : x
  2. Step 2: Convert to fraction form
    638.38/956.91 = 419.18/x
  3. Step 3: Cross multiply
    638.38x = 956.91 × 419.18
  4. Step 4: Simplify right side
    638.38x = 401,114.32
  5. Step 5: Solve for x
    x = 401,114.32/638.38
  6. Step 6: Final answer
    x = 628.33

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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.