Finding the Third Proportional to 64,638.56 and 90,410.06

Step by Step Solution

1. Step 1: Write the proportion equation
   64,638.56 : 90,410.06 = 90,410.06 : x
2. Step 2: Convert to fraction form
   64,638.56/90,410.06 = 90,410.06/x
3. Step 3: Cross multiply
   64,638.56x = 90,410.06 × 90,410.06
4. Step 4: Simplify right side
   64,638.56x = 8,173,979,401.25
5. Step 5: Solve for x
   x = 8,173,979,401.25/64,638.56
6. Step 6: Final answer
   x = 126,456.70