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Finding the Fourth Proportional to 388.80, 533.06 and 381.86

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Solution

The fourth proportional to 388.80, 533.06 and 381.86 is: 523.54

Step by Step Solution

  1. Step 1: Write the proportion equation
    388.80 : 533.06 = 381.86 : x
  2. Step 2: Convert to fraction form
    388.80/533.06 = 381.86/x
  3. Step 3: Cross multiply
    388.80x = 533.06 × 381.86
  4. Step 4: Simplify right side
    388.80x = 203,554.29
  5. Step 5: Solve for x
    x = 203,554.29/388.80
  6. Step 6: Final answer
    x = 523.54

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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.