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Finding the Fourth Proportional to 640.09, 960.34 and 478.09

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Solution

The fourth proportional to 640.09, 960.34 and 478.09 is: 717.29

Step by Step Solution

  1. Step 1: Write the proportion equation
    640.09 : 960.34 = 478.09 : x
  2. Step 2: Convert to fraction form
    640.09/960.34 = 478.09/x
  3. Step 3: Cross multiply
    640.09x = 960.34 × 478.09
  4. Step 4: Simplify right side
    640.09x = 459,128.95
  5. Step 5: Solve for x
    x = 459,128.95/640.09
  6. Step 6: Final answer
    x = 717.29

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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.