Finding the Third Proportional to 503,860.50 and 780,129

Step by Step Solution

1. Step 1: Write the proportion equation
   503,860.50 : 780,129 = 780,129 : x
2. Step 2: Convert to fraction form
   503,860.50/780,129 = 780,129/x
3. Step 3: Cross multiply
   503,860.50x = 780,129 × 780,129
4. Step 4: Simplify right side
   503,860.50x = 608,601,256,641
5. Step 5: Solve for x
   x = 608,601,256,641/503,860.50
6. Step 6: Final answer
   x = 1,207,876.50