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Finding the Fourth Proportional to 640.40, 883.79 and 374.85

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Solution

The fourth proportional to 640.40, 883.79 and 374.85 is: 517.32

Step by Step Solution

  1. Step 1: Write the proportion equation
    640.40 : 883.79 = 374.85 : x
  2. Step 2: Convert to fraction form
    640.40/883.79 = 374.85/x
  3. Step 3: Cross multiply
    640.40x = 883.79 × 374.85
  4. Step 4: Simplify right side
    640.40x = 331,288.68
  5. Step 5: Solve for x
    x = 331,288.68/640.40
  6. Step 6: Final answer
    x = 517.32

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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.