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Finding the Fourth Proportional to 643.54, 963.87 and 399.37

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Solution

The fourth proportional to 643.54, 963.87 and 399.37 is: 598.16

Step by Step Solution

  1. Step 1: Write the proportion equation
    643.54 : 963.87 = 399.37 : x
  2. Step 2: Convert to fraction form
    643.54/963.87 = 399.37/x
  3. Step 3: Cross multiply
    643.54x = 963.87 × 399.37
  4. Step 4: Simplify right side
    643.54x = 384,940.76
  5. Step 5: Solve for x
    x = 384,940.76/643.54
  6. Step 6: Final answer
    x = 598.16

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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.