Finding the Third Proportional to 67,138.50 and 90,859.50

Step by Step Solution

1. Step 1: Write the proportion equation
   67,138.50 : 90,859.50 = 90,859.50 : x
2. Step 2: Convert to fraction form
   67,138.50/90,859.50 = 90,859.50/x
3. Step 3: Cross multiply
   67,138.50x = 90,859.50 × 90,859.50
4. Step 4: Simplify right side
   67,138.50x = 8,255,448,740.25
5. Step 5: Solve for x
   x = 8,255,448,740.25/67,138.50
6. Step 6: Final answer
   x = 122,961.47