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Finding the Fourth Proportional to 640.12, 883.55 and 378.28

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Solution

The fourth proportional to 640.12, 883.55 and 378.28 is: 522.14

Step by Step Solution

  1. Step 1: Write the proportion equation
    640.12 : 883.55 = 378.28 : x
  2. Step 2: Convert to fraction form
    640.12/883.55 = 378.28/x
  3. Step 3: Cross multiply
    640.12x = 883.55 × 378.28
  4. Step 4: Simplify right side
    640.12x = 334,229.29
  5. Step 5: Solve for x
    x = 334,229.29/640.12
  6. Step 6: Final answer
    x = 522.14

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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.