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Finding the Fourth Proportional to 639.90, 883.05 and 360.13

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Solution

The fourth proportional to 639.90, 883.05 and 360.13 is: 496.97

Step by Step Solution

  1. Step 1: Write the proportion equation
    639.90 : 883.05 = 360.13 : x
  2. Step 2: Convert to fraction form
    639.90/883.05 = 360.13/x
  3. Step 3: Cross multiply
    639.90x = 883.05 × 360.13
  4. Step 4: Simplify right side
    639.90x = 318,012.92
  5. Step 5: Solve for x
    x = 318,012.92/639.90
  6. Step 6: Final answer
    x = 496.97

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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.