Finding the Third Proportional to 311,607 and 666,407.25

Step by Step Solution

1. Step 1: Write the proportion equation
   311,607 : 666,407.25 = 666,407.25 : x
2. Step 2: Convert to fraction form
   311,607/666,407.25 = 666,407.25/x
3. Step 3: Cross multiply
   311,607x = 666,407.25 × 666,407.25
4. Step 4: Simplify right side
   311,607x = 444,098,622,852.56
5. Step 5: Solve for x
   x = 444,098,622,852.56/311,607
6. Step 6: Final answer
   x = 1,425,188.21