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Finding the Fourth Proportional to 643.38, 963.29 and 486.74

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Solution

The fourth proportional to 643.38, 963.29 and 486.74 is: 728.77

Step by Step Solution

  1. Step 1: Write the proportion equation
    643.38 : 963.29 = 486.74 : x
  2. Step 2: Convert to fraction form
    643.38/963.29 = 486.74/x
  3. Step 3: Cross multiply
    643.38x = 963.29 × 486.74
  4. Step 4: Simplify right side
    643.38x = 468,875.40
  5. Step 5: Solve for x
    x = 468,875.40/643.38
  6. Step 6: Final answer
    x = 728.77

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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.