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Finding the Fourth Proportional to 639.45, 958.86 and 228.47

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Solution

The fourth proportional to 639.45, 958.86 and 228.47 is: 342.58

Step by Step Solution

  1. Step 1: Write the proportion equation
    639.45 : 958.86 = 228.47 : x
  2. Step 2: Convert to fraction form
    639.45/958.86 = 228.47/x
  3. Step 3: Cross multiply
    639.45x = 958.86 × 228.47
  4. Step 4: Simplify right side
    639.45x = 219,065.95
  5. Step 5: Solve for x
    x = 219,065.95/639.45
  6. Step 6: Final answer
    x = 342.58

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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.