Finding the Third Proportional to 276,991.50 and 612,109.50

Step by Step Solution

1. Step 1: Write the proportion equation
   276,991.50 : 612,109.50 = 612,109.50 : x
2. Step 2: Convert to fraction form
   276,991.50/612,109.50 = 612,109.50/x
3. Step 3: Cross multiply
   276,991.50x = 612,109.50 × 612,109.50
4. Step 4: Simplify right side
   276,991.50x = 374,678,039,990.25
5. Step 5: Solve for x
   x = 374,678,039,990.25/276,991.50
6. Step 6: Final answer
   x = 1,352,669.81