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Finding the Fourth Proportional to 639.95, 883.24 and 378.11

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Solution

The fourth proportional to 639.95, 883.24 and 378.11 is: 521.86

Step by Step Solution

  1. Step 1: Write the proportion equation
    639.95 : 883.24 = 378.11 : x
  2. Step 2: Convert to fraction form
    639.95/883.24 = 378.11/x
  3. Step 3: Cross multiply
    639.95x = 883.24 × 378.11
  4. Step 4: Simplify right side
    639.95x = 333,963.14
  5. Step 5: Solve for x
    x = 333,963.14/639.95
  6. Step 6: Final answer
    x = 521.86

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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.