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Finding the Fourth Proportional to 640.69, 884.18 and 378.79

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Solution

The fourth proportional to 640.69, 884.18 and 378.79 is: 522.75

Step by Step Solution

  1. Step 1: Write the proportion equation
    640.69 : 884.18 = 378.79 : x
  2. Step 2: Convert to fraction form
    640.69/884.18 = 378.79/x
  3. Step 3: Cross multiply
    640.69x = 884.18 × 378.79
  4. Step 4: Simplify right side
    640.69x = 334,918.54
  5. Step 5: Solve for x
    x = 334,918.54/640.69
  6. Step 6: Final answer
    x = 522.75

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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.