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Finding the Fourth Proportional to 648.28, 893.64 and 399.43

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Solution

The fourth proportional to 648.28, 893.64 and 399.43 is: 550.61

Step by Step Solution

  1. Step 1: Write the proportion equation
    648.28 : 893.64 = 399.43 : x
  2. Step 2: Convert to fraction form
    648.28/893.64 = 399.43/x
  3. Step 3: Cross multiply
    648.28x = 893.64 × 399.43
  4. Step 4: Simplify right side
    648.28x = 356,946.63
  5. Step 5: Solve for x
    x = 356,946.63/648.28
  6. Step 6: Final answer
    x = 550.61

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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.