Finding the Third Proportional to 312,151.50 and 671,647.50

Step by Step Solution

1. Step 1: Write the proportion equation
   312,151.50 : 671,647.50 = 671,647.50 : x
2. Step 2: Convert to fraction form
   312,151.50/671,647.50 = 671,647.50/x
3. Step 3: Cross multiply
   312,151.50x = 671,647.50 × 671,647.50
4. Step 4: Simplify right side
   312,151.50x = 451,110,364,256.25
5. Step 5: Solve for x
   x = 451,110,364,256.25/312,151.50
6. Step 6: Final answer
   x = 1,445,164.81