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Finding the Fourth Proportional to 640.70, 960.73 and 380.73

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Solution

The fourth proportional to 640.70, 960.73 and 380.73 is: 570.90

Step by Step Solution

  1. Step 1: Write the proportion equation
    640.70 : 960.73 = 380.73 : x
  2. Step 2: Convert to fraction form
    640.70/960.73 = 380.73/x
  3. Step 3: Cross multiply
    640.70x = 960.73 × 380.73
  4. Step 4: Simplify right side
    640.70x = 365,778.73
  5. Step 5: Solve for x
    x = 365,778.73/640.70
  6. Step 6: Final answer
    x = 570.90

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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.