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Finding the Fourth Proportional to 640.37, 960.83 and 409.19

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Solution

The fourth proportional to 640.37, 960.83 and 409.19 is: 613.95

Step by Step Solution

  1. Step 1: Write the proportion equation
    640.37 : 960.83 = 409.19 : x
  2. Step 2: Convert to fraction form
    640.37/960.83 = 409.19/x
  3. Step 3: Cross multiply
    640.37x = 960.83 × 409.19
  4. Step 4: Simplify right side
    640.37x = 393,156.71
  5. Step 5: Solve for x
    x = 393,156.71/640.37
  6. Step 6: Final answer
    x = 613.95

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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.