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Finding the Fourth Proportional to 639.25, 958.49 and 228.31

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Solution

The fourth proportional to 639.25, 958.49 and 228.31 is: 342.32

Step by Step Solution

  1. Step 1: Write the proportion equation
    639.25 : 958.49 = 228.31 : x
  2. Step 2: Convert to fraction form
    639.25/958.49 = 228.31/x
  3. Step 3: Cross multiply
    639.25x = 958.49 × 228.31
  4. Step 4: Simplify right side
    639.25x = 218,826.92
  5. Step 5: Solve for x
    x = 218,826.92/639.25
  6. Step 6: Final answer
    x = 342.32

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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.