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Finding the Fourth Proportional to 643.08, 963.56 and 399.18

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Solution

The fourth proportional to 643.08, 963.56 and 399.18 is: 598.11

Step by Step Solution

  1. Step 1: Write the proportion equation
    643.08 : 963.56 = 399.18 : x
  2. Step 2: Convert to fraction form
    643.08/963.56 = 399.18/x
  3. Step 3: Cross multiply
    643.08x = 963.56 × 399.18
  4. Step 4: Simplify right side
    643.08x = 384,633.88
  5. Step 5: Solve for x
    x = 384,633.88/643.08
  6. Step 6: Final answer
    x = 598.11

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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.