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Finding the Fourth Proportional to 640.71, 883.89 and 378.59

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Solution

The fourth proportional to 640.71, 883.89 and 378.59 is: 522.28

Step by Step Solution

  1. Step 1: Write the proportion equation
    640.71 : 883.89 = 378.59 : x
  2. Step 2: Convert to fraction form
    640.71/883.89 = 378.59/x
  3. Step 3: Cross multiply
    640.71x = 883.89 × 378.59
  4. Step 4: Simplify right side
    640.71x = 334,627.50
  5. Step 5: Solve for x
    x = 334,627.50/640.71
  6. Step 6: Final answer
    x = 522.28

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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.