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Finding the Fourth Proportional to 640.47, 959.49 and 379.92

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Solution

The fourth proportional to 640.47, 959.49 and 379.92 is: 569.16

Step by Step Solution

  1. Step 1: Write the proportion equation
    640.47 : 959.49 = 379.92 : x
  2. Step 2: Convert to fraction form
    640.47/959.49 = 379.92/x
  3. Step 3: Cross multiply
    640.47x = 959.49 × 379.92
  4. Step 4: Simplify right side
    640.47x = 364,529.44
  5. Step 5: Solve for x
    x = 364,529.44/640.47
  6. Step 6: Final answer
    x = 569.16

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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.