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Finding the Fourth Proportional to 388.06, 535.41 and 289.85

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Solution

The fourth proportional to 388.06, 535.41 and 289.85 is: 399.90

Step by Step Solution

  1. Step 1: Write the proportion equation
    388.06 : 535.41 = 289.85 : x
  2. Step 2: Convert to fraction form
    388.06/535.41 = 289.85/x
  3. Step 3: Cross multiply
    388.06x = 535.41 × 289.85
  4. Step 4: Simplify right side
    388.06x = 155,185.91
  5. Step 5: Solve for x
    x = 155,185.91/388.06
  6. Step 6: Final answer
    x = 399.90

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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.