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Finding the Fourth Proportional to 638.99, 956.64 and 330.11

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Solution

The fourth proportional to 638.99, 956.64 and 330.11 is: 494.21

Step by Step Solution

  1. Step 1: Write the proportion equation
    638.99 : 956.64 = 330.11 : x
  2. Step 2: Convert to fraction form
    638.99/956.64 = 330.11/x
  3. Step 3: Cross multiply
    638.99x = 956.64 × 330.11
  4. Step 4: Simplify right side
    638.99x = 315,796.43
  5. Step 5: Solve for x
    x = 315,796.43/638.99
  6. Step 6: Final answer
    x = 494.21

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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.