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Finding the Fourth Proportional to 640.35, 883.76 and 378.38

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Solution

The fourth proportional to 640.35, 883.76 and 378.38 is: 522.21

Step by Step Solution

  1. Step 1: Write the proportion equation
    640.35 : 883.76 = 378.38 : x
  2. Step 2: Convert to fraction form
    640.35/883.76 = 378.38/x
  3. Step 3: Cross multiply
    640.35x = 883.76 × 378.38
  4. Step 4: Simplify right side
    640.35x = 334,392.69
  5. Step 5: Solve for x
    x = 334,392.69/640.35
  6. Step 6: Final answer
    x = 522.21

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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.