Finding the Third Proportional to 378,706.50 and 821,790

Step by Step Solution

1. Step 1: Write the proportion equation
   378,706.50 : 821,790 = 821,790 : x
2. Step 2: Convert to fraction form
   378,706.50/821,790 = 821,790/x
3. Step 3: Cross multiply
   378,706.50x = 821,790 × 821,790
4. Step 4: Simplify right side
   378,706.50x = 675,338,804,100
5. Step 5: Solve for x
   x = 675,338,804,100/378,706.50
6. Step 6: Final answer
   x = 1,783,277.56