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Finding the Fourth Proportional to 445.43, 613.28 and 378.90

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Solution

The fourth proportional to 445.43, 613.28 and 378.90 is: 521.68

Step by Step Solution

  1. Step 1: Write the proportion equation
    445.43 : 613.28 = 378.90 : x
  2. Step 2: Convert to fraction form
    445.43/613.28 = 378.90/x
  3. Step 3: Cross multiply
    445.43x = 613.28 × 378.90
  4. Step 4: Simplify right side
    445.43x = 232,369.90
  5. Step 5: Solve for x
    x = 232,369.90/445.43
  6. Step 6: Final answer
    x = 521.68

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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.