Finding the Third Proportional to 428,157 and 666,742.50

Step by Step Solution

1. Step 1: Write the proportion equation
   428,157 : 666,742.50 = 666,742.50 : x
2. Step 2: Convert to fraction form
   428,157/666,742.50 = 666,742.50/x
3. Step 3: Cross multiply
   428,157x = 666,742.50 × 666,742.50
4. Step 4: Simplify right side
   428,157x = 444,545,561,306.25
5. Step 5: Solve for x
   x = 444,545,561,306.25/428,157
6. Step 6: Final answer
   x = 1,038,276.99