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Finding the Third Proportional to 128,430 and 199,639.50

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Solution

The third proportional to 128,430 and 199,639.50 is: 310,331.93

Step by Step Solution

  1. Step 1: Write the proportion equation
    128,430 : 199,639.50 = 199,639.50 : x
  2. Step 2: Convert to fraction form
    128,430/199,639.50 = 199,639.50/x
  3. Step 3: Cross multiply
    128,430x = 199,639.50 × 199,639.50
  4. Step 4: Simplify right side
    128,430x = 39,855,929,960.25
  5. Step 5: Solve for x
    x = 39,855,929,960.25/128,430
  6. Step 6: Final answer
    x = 310,331.93

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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.