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Finding the Fourth Proportional to 640.49, 883.90 and 378.50

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Solution

The fourth proportional to 640.49, 883.90 and 378.50 is: 522.34

Step by Step Solution

  1. Step 1: Write the proportion equation
    640.49 : 883.90 = 378.50 : x
  2. Step 2: Convert to fraction form
    640.49/883.90 = 378.50/x
  3. Step 3: Cross multiply
    640.49x = 883.90 × 378.50
  4. Step 4: Simplify right side
    640.49x = 334,556.15
  5. Step 5: Solve for x
    x = 334,556.15/640.49
  6. Step 6: Final answer
    x = 522.34

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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.