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Finding the Fourth Proportional to 640.41, 883.81 and 378.47

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Solution

The fourth proportional to 640.41, 883.81 and 378.47 is: 522.32

Step by Step Solution

  1. Step 1: Write the proportion equation
    640.41 : 883.81 = 378.47 : x
  2. Step 2: Convert to fraction form
    640.41/883.81 = 378.47/x
  3. Step 3: Cross multiply
    640.41x = 883.81 × 378.47
  4. Step 4: Simplify right side
    640.41x = 334,498.25
  5. Step 5: Solve for x
    x = 334,498.25/640.41
  6. Step 6: Final answer
    x = 522.32

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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.