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Finding the Fourth Proportional to 640.63, 883.29 and 378.55

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Solution

The fourth proportional to 640.63, 883.29 and 378.55 is: 521.94

Step by Step Solution

  1. Step 1: Write the proportion equation
    640.63 : 883.29 = 378.55 : x
  2. Step 2: Convert to fraction form
    640.63/883.29 = 378.55/x
  3. Step 3: Cross multiply
    640.63x = 883.29 × 378.55
  4. Step 4: Simplify right side
    640.63x = 334,369.43
  5. Step 5: Solve for x
    x = 334,369.43/640.63
  6. Step 6: Final answer
    x = 521.94

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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.