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Finding the Fourth Proportional to 639.08, 881.90 and 359.28

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Solution

The fourth proportional to 639.08, 881.90 and 359.28 is: 495.79

Step by Step Solution

  1. Step 1: Write the proportion equation
    639.08 : 881.90 = 359.28 : x
  2. Step 2: Convert to fraction form
    639.08/881.90 = 359.28/x
  3. Step 3: Cross multiply
    639.08x = 881.90 × 359.28
  4. Step 4: Simplify right side
    639.08x = 316,849.03
  5. Step 5: Solve for x
    x = 316,849.03/639.08
  6. Step 6: Final answer
    x = 495.79

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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.