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Finding the Fourth Proportional to 643.46, 964.98 and 539.78

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Solution

The fourth proportional to 643.46, 964.98 and 539.78 is: 809.49

Step by Step Solution

  1. Step 1: Write the proportion equation
    643.46 : 964.98 = 539.78 : x
  2. Step 2: Convert to fraction form
    643.46/964.98 = 539.78/x
  3. Step 3: Cross multiply
    643.46x = 964.98 × 539.78
  4. Step 4: Simplify right side
    643.46x = 520,872.08
  5. Step 5: Solve for x
    x = 520,872.08/643.46
  6. Step 6: Final answer
    x = 809.49

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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.