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Finding the Fourth Proportional to 640.70, 961.56 and 380.82

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Solution

The fourth proportional to 640.70, 961.56 and 380.82 is: 571.53

Step by Step Solution

  1. Step 1: Write the proportion equation
    640.70 : 961.56 = 380.82 : x
  2. Step 2: Convert to fraction form
    640.70/961.56 = 380.82/x
  3. Step 3: Cross multiply
    640.70x = 961.56 × 380.82
  4. Step 4: Simplify right side
    640.70x = 366,181.28
  5. Step 5: Solve for x
    x = 366,181.28/640.70
  6. Step 6: Final answer
    x = 571.53

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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.