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Finding the Fourth Proportional to 639.20, 958.48 and 228.32

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Solution

The fourth proportional to 639.20, 958.48 and 228.32 is: 342.37

Step by Step Solution

  1. Step 1: Write the proportion equation
    639.20 : 958.48 = 228.32 : x
  2. Step 2: Convert to fraction form
    639.20/958.48 = 228.32/x
  3. Step 3: Cross multiply
    639.20x = 958.48 × 228.32
  4. Step 4: Simplify right side
    639.20x = 218,840.15
  5. Step 5: Solve for x
    x = 218,840.15/639.20
  6. Step 6: Final answer
    x = 342.37

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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.