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Finding the Fourth Proportional to 639.07, 881.87 and 359.28

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Solution

The fourth proportional to 639.07, 881.87 and 359.28 is: 495.78

Step by Step Solution

  1. Step 1: Write the proportion equation
    639.07 : 881.87 = 359.28 : x
  2. Step 2: Convert to fraction form
    639.07/881.87 = 359.28/x
  3. Step 3: Cross multiply
    639.07x = 881.87 × 359.28
  4. Step 4: Simplify right side
    639.07x = 316,836.46
  5. Step 5: Solve for x
    x = 316,836.46/639.07
  6. Step 6: Final answer
    x = 495.78

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.