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Finding the Fourth Proportional to 638.91, 958.54 and 228.09

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Solution

The fourth proportional to 638.91, 958.54 and 228.09 is: 342.19

Step by Step Solution

  1. Step 1: Write the proportion equation
    638.91 : 958.54 = 228.09 : x
  2. Step 2: Convert to fraction form
    638.91/958.54 = 228.09/x
  3. Step 3: Cross multiply
    638.91x = 958.54 × 228.09
  4. Step 4: Simplify right side
    638.91x = 218,631.45
  5. Step 5: Solve for x
    x = 218,631.45/638.91
  6. Step 6: Final answer
    x = 342.19

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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.