Finding the Third Proportional to 400,680 and 620,136

Step by Step Solution

1. Step 1: Write the proportion equation
   400,680 : 620,136 = 620,136 : x
2. Step 2: Convert to fraction form
   400,680/620,136 = 620,136/x
3. Step 3: Cross multiply
   400,680x = 620,136 × 620,136
4. Step 4: Simplify right side
   400,680x = 384,568,658,496
5. Step 5: Solve for x
   x = 384,568,658,496/400,680
6. Step 6: Final answer
   x = 959,790.00