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Finding the Fourth Proportional to 422.01, 631.40 and 387.59

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Solution

The fourth proportional to 422.01, 631.40 and 387.59 is: 579.89

Step by Step Solution

  1. Step 1: Write the proportion equation
    422.01 : 631.40 = 387.59 : x
  2. Step 2: Convert to fraction form
    422.01/631.40 = 387.59/x
  3. Step 3: Cross multiply
    422.01x = 631.40 × 387.59
  4. Step 4: Simplify right side
    422.01x = 244,719.23
  5. Step 5: Solve for x
    x = 244,719.23/422.01
  6. Step 6: Final answer
    x = 579.89

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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.