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Finding the Fourth Proportional to 611.91, 918.23 and 287.28

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Solution

The fourth proportional to 611.91, 918.23 and 287.28 is: 431.09

Step by Step Solution

  1. Step 1: Write the proportion equation
    611.91 : 918.23 = 287.28 : x
  2. Step 2: Convert to fraction form
    611.91/918.23 = 287.28/x
  3. Step 3: Cross multiply
    611.91x = 918.23 × 287.28
  4. Step 4: Simplify right side
    611.91x = 263,787.68
  5. Step 5: Solve for x
    x = 263,787.68/611.91
  6. Step 6: Final answer
    x = 431.09

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.