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Finding the Fourth Proportional to 421.91, 631.64 and 379.99

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Solution

The fourth proportional to 421.91, 631.64 and 379.99 is: 568.88

Step by Step Solution

  1. Step 1: Write the proportion equation
    421.91 : 631.64 = 379.99 : x
  2. Step 2: Convert to fraction form
    421.91/631.64 = 379.99/x
  3. Step 3: Cross multiply
    421.91x = 631.64 × 379.99
  4. Step 4: Simplify right side
    421.91x = 240,016.88
  5. Step 5: Solve for x
    x = 240,016.88/421.91
  6. Step 6: Final answer
    x = 568.88

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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.