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Finding the Fourth Proportional to 287.65, 396.83 and 221.27

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Solution

The fourth proportional to 287.65, 396.83 and 221.27 is: 305.26

Step by Step Solution

  1. Step 1: Write the proportion equation
    287.65 : 396.83 = 221.27 : x
  2. Step 2: Convert to fraction form
    287.65/396.83 = 221.27/x
  3. Step 3: Cross multiply
    287.65x = 396.83 × 221.27
  4. Step 4: Simplify right side
    287.65x = 87,805.47
  5. Step 5: Solve for x
    x = 87,805.47/287.65
  6. Step 6: Final answer
    x = 305.26

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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.