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Finding the Fourth Proportional to 638.79, 958.28 and 205.98

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Solution

The fourth proportional to 638.79, 958.28 and 205.98 is: 309.00

Step by Step Solution

  1. Step 1: Write the proportion equation
    638.79 : 958.28 = 205.98 : x
  2. Step 2: Convert to fraction form
    638.79/958.28 = 205.98/x
  3. Step 3: Cross multiply
    638.79x = 958.28 × 205.98
  4. Step 4: Simplify right side
    638.79x = 197,385.48
  5. Step 5: Solve for x
    x = 197,385.48/638.79
  6. Step 6: Final answer
    x = 309.00

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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.