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Finding the Fourth Proportional to 387.06, 533.97 and 287.70

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Solution

The fourth proportional to 387.06, 533.97 and 287.70 is: 396.90

Step by Step Solution

  1. Step 1: Write the proportion equation
    387.06 : 533.97 = 287.70 : x
  2. Step 2: Convert to fraction form
    387.06/533.97 = 287.70/x
  3. Step 3: Cross multiply
    387.06x = 533.97 × 287.70
  4. Step 4: Simplify right side
    387.06x = 153,623.17
  5. Step 5: Solve for x
    x = 153,623.17/387.06
  6. Step 6: Final answer
    x = 396.90

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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.