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Finding the Third Proportional to 128.50 and 219

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Solution

The third proportional to 128.50 and 219 is: 373.24

Step by Step Solution

  1. Step 1: Write the proportion equation
    128.50 : 219 = 219 : x
  2. Step 2: Convert to fraction form
    128.50/219 = 219/x
  3. Step 3: Cross multiply
    128.50x = 219 × 219
  4. Step 4: Simplify right side
    128.50x = 47,961
  5. Step 5: Solve for x
    x = 47,961/128.50
  6. Step 6: Final answer
    x = 373.24

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Why These Related Problems?

These problems maintain the same ratio (1.70) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.