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Finding the Fourth Proportional to 640.79, 885.92 and 445.76

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Solution

The fourth proportional to 640.79, 885.92 and 445.76 is: 616.28

Step by Step Solution

  1. Step 1: Write the proportion equation
    640.79 : 885.92 = 445.76 : x
  2. Step 2: Convert to fraction form
    640.79/885.92 = 445.76/x
  3. Step 3: Cross multiply
    640.79x = 885.92 × 445.76
  4. Step 4: Simplify right side
    640.79x = 394,901.04
  5. Step 5: Solve for x
    x = 394,901.04/640.79
  6. Step 6: Final answer
    x = 616.28

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.