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Finding the Fourth Proportional to 643.39, 964.94 and 437.90

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Solution

The fourth proportional to 643.39, 964.94 and 437.90 is: 656.74

Step by Step Solution

  1. Step 1: Write the proportion equation
    643.39 : 964.94 = 437.90 : x
  2. Step 2: Convert to fraction form
    643.39/964.94 = 437.90/x
  3. Step 3: Cross multiply
    643.39x = 964.94 × 437.90
  4. Step 4: Simplify right side
    643.39x = 422,540.21
  5. Step 5: Solve for x
    x = 422,540.21/643.39
  6. Step 6: Final answer
    x = 656.74

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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.