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Finding the Fourth Proportional to 640.46, 883.79 and 378.42

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Solution

The fourth proportional to 640.46, 883.79 and 378.42 is: 522.20

Step by Step Solution

  1. Step 1: Write the proportion equation
    640.46 : 883.79 = 378.42 : x
  2. Step 2: Convert to fraction form
    640.46/883.79 = 378.42/x
  3. Step 3: Cross multiply
    640.46x = 883.79 × 378.42
  4. Step 4: Simplify right side
    640.46x = 334,443.93
  5. Step 5: Solve for x
    x = 334,443.93/640.46
  6. Step 6: Final answer
    x = 522.20

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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.