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Finding the Fourth Proportional to 640.20, 884.34 and 570.54

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Solution

The fourth proportional to 640.20, 884.34 and 570.54 is: 788.12

Step by Step Solution

  1. Step 1: Write the proportion equation
    640.20 : 884.34 = 570.54 : x
  2. Step 2: Convert to fraction form
    640.20/884.34 = 570.54/x
  3. Step 3: Cross multiply
    640.20x = 884.34 × 570.54
  4. Step 4: Simplify right side
    640.20x = 504,551.34
  5. Step 5: Solve for x
    x = 504,551.34/640.20
  6. Step 6: Final answer
    x = 788.12

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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.