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Finding the Fourth Proportional to 639.36, 960.63 and 408.34

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Solution

The fourth proportional to 639.36, 960.63 and 408.34 is: 613.52

Step by Step Solution

  1. Step 1: Write the proportion equation
    639.36 : 960.63 = 408.34 : x
  2. Step 2: Convert to fraction form
    639.36/960.63 = 408.34/x
  3. Step 3: Cross multiply
    639.36x = 960.63 × 408.34
  4. Step 4: Simplify right side
    639.36x = 392,263.32
  5. Step 5: Solve for x
    x = 392,263.32/639.36
  6. Step 6: Final answer
    x = 613.52

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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.