Finding the Third Proportional to 82,781.50 and 128,151.25

Step by Step Solution

1. Step 1: Write the proportion equation
   82,781.50 : 128,151.25 = 128,151.25 : x
2. Step 2: Convert to fraction form
   82,781.50/128,151.25 = 128,151.25/x
3. Step 3: Cross multiply
   82,781.50x = 128,151.25 × 128,151.25
4. Step 4: Simplify right side
   82,781.50x = 16,422,742,876.56
5. Step 5: Solve for x
   x = 16,422,742,876.56/82,781.50
6. Step 6: Final answer
   x = 198,386.63