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Finding the Fourth Proportional to 640.31, 959.56 and 292.79

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Solution

The fourth proportional to 640.31, 959.56 and 292.79 is: 438.77

Step by Step Solution

  1. Step 1: Write the proportion equation
    640.31 : 959.56 = 292.79 : x
  2. Step 2: Convert to fraction form
    640.31/959.56 = 292.79/x
  3. Step 3: Cross multiply
    640.31x = 959.56 × 292.79
  4. Step 4: Simplify right side
    640.31x = 280,949.57
  5. Step 5: Solve for x
    x = 280,949.57/640.31
  6. Step 6: Final answer
    x = 438.77

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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.