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Finding the Fourth Proportional to 640.11, 883.32 and 378.12

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Solution

The fourth proportional to 640.11, 883.32 and 378.12 is: 521.79

Step by Step Solution

  1. Step 1: Write the proportion equation
    640.11 : 883.32 = 378.12 : x
  2. Step 2: Convert to fraction form
    640.11/883.32 = 378.12/x
  3. Step 3: Cross multiply
    640.11x = 883.32 × 378.12
  4. Step 4: Simplify right side
    640.11x = 334,000.96
  5. Step 5: Solve for x
    x = 334,000.96/640.11
  6. Step 6: Final answer
    x = 521.79

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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.