Finding the Third Proportional to 2,139 and 5,077.50

Step by Step Solution

1. Step 1: Write the proportion equation
   2,139 : 5,077.50 = 5,077.50 : x
2. Step 2: Convert to fraction form
   2,139/5,077.50 = 5,077.50/x
3. Step 3: Cross multiply
   2,139x = 5,077.50 × 5,077.50
4. Step 4: Simplify right side
   2,139x = 25,781,006.25
5. Step 5: Solve for x
   x = 25,781,006.25/2,139
6. Step 6: Final answer
   x = 12,052.83