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Finding the Fourth Proportional to 643.32, 963.42 and 399.09

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Solution

The fourth proportional to 643.32, 963.42 and 399.09 is: 597.67

Step by Step Solution

  1. Step 1: Write the proportion equation
    643.32 : 963.42 = 399.09 : x
  2. Step 2: Convert to fraction form
    643.32/963.42 = 399.09/x
  3. Step 3: Cross multiply
    643.32x = 963.42 × 399.09
  4. Step 4: Simplify right side
    643.32x = 384,491.29
  5. Step 5: Solve for x
    x = 384,491.29/643.32
  6. Step 6: Final answer
    x = 597.67

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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.