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Finding the Fourth Proportional to 611.70, 918.34 and 287.28

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Solution

The fourth proportional to 611.70, 918.34 and 287.28 is: 431.29

Step by Step Solution

  1. Step 1: Write the proportion equation
    611.70 : 918.34 = 287.28 : x
  2. Step 2: Convert to fraction form
    611.70/918.34 = 287.28/x
  3. Step 3: Cross multiply
    611.70x = 918.34 × 287.28
  4. Step 4: Simplify right side
    611.70x = 263,820.72
  5. Step 5: Solve for x
    x = 263,820.72/611.70
  6. Step 6: Final answer
    x = 431.29

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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.