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Finding the Fourth Proportional to 639.89, 959.59 and 228.92

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Solution

The fourth proportional to 639.89, 959.59 and 228.92 is: 343.29

Step by Step Solution

  1. Step 1: Write the proportion equation
    639.89 : 959.59 = 228.92 : x
  2. Step 2: Convert to fraction form
    639.89/959.59 = 228.92/x
  3. Step 3: Cross multiply
    639.89x = 959.59 × 228.92
  4. Step 4: Simplify right side
    639.89x = 219,669.34
  5. Step 5: Solve for x
    x = 219,669.34/639.89
  6. Step 6: Final answer
    x = 343.29

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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.