Finding the Third Proportional to 64,690.50 and 90,649.50

Step by Step Solution

1. Step 1: Write the proportion equation
   64,690.50 : 90,649.50 = 90,649.50 : x
2. Step 2: Convert to fraction form
   64,690.50/90,649.50 = 90,649.50/x
3. Step 3: Cross multiply
   64,690.50x = 90,649.50 × 90,649.50
4. Step 4: Simplify right side
   64,690.50x = 8,217,331,850.25
5. Step 5: Solve for x
   x = 8,217,331,850.25/64,690.50
6. Step 6: Final answer
   x = 127,025.33