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Finding the Fourth Proportional to 385.43, 528.37 and 378.45

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Solution

The fourth proportional to 385.43, 528.37 and 378.45 is: 518.81

Step by Step Solution

  1. Step 1: Write the proportion equation
    385.43 : 528.37 = 378.45 : x
  2. Step 2: Convert to fraction form
    385.43/528.37 = 378.45/x
  3. Step 3: Cross multiply
    385.43x = 528.37 × 378.45
  4. Step 4: Simplify right side
    385.43x = 199,960.68
  5. Step 5: Solve for x
    x = 199,960.68/385.43
  6. Step 6: Final answer
    x = 518.81

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Why These Related Problems?

These problems maintain the same ratio (1.37) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.