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Finding the Fourth Proportional to 639.91, 883.09 and 360.21

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Solution

The fourth proportional to 639.91, 883.09 and 360.21 is: 497.10

Step by Step Solution

  1. Step 1: Write the proportion equation
    639.91 : 883.09 = 360.21 : x
  2. Step 2: Convert to fraction form
    639.91/883.09 = 360.21/x
  3. Step 3: Cross multiply
    639.91x = 883.09 × 360.21
  4. Step 4: Simplify right side
    639.91x = 318,097.85
  5. Step 5: Solve for x
    x = 318,097.85/639.91
  6. Step 6: Final answer
    x = 497.10

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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.