Finding the Third Proportional to 312,321,856.50 and 685,925,581.50

Step by Step Solution

1. Step 1: Write the proportion equation
   312,321,856.50 : 685,925,581.50 = 685,925,581.50 : x
2. Step 2: Convert to fraction form
   312,321,856.50/685,925,581.50 = 685,925,581.50/x
3. Step 3: Cross multiply
   312,321,856.50x = 685,925,581.50 × 685,925,581.50
4. Step 4: Simplify right side
   312,321,856.50x = 470,493,903,356,113,152
5. Step 5: Solve for x
   x = 470,493,903,356,113,152/312,321,856.50
6. Step 6: Final answer
   x = 1,506,439,250.29