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Finding the Third Proportional to 128.50 and 199

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Solution

The third proportional to 128.50 and 199 is: 308.18

Step by Step Solution

  1. Step 1: Write the proportion equation
    128.50 : 199 = 199 : x
  2. Step 2: Convert to fraction form
    128.50/199 = 199/x
  3. Step 3: Cross multiply
    128.50x = 199 × 199
  4. Step 4: Simplify right side
    128.50x = 39,601
  5. Step 5: Solve for x
    x = 39,601/128.50
  6. Step 6: Final answer
    x = 308.18

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Why These Related Problems?

These problems maintain the same ratio (1.55) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.