Finding the Fourth Proportional to 123,629.78, 170,630.96 and 72,642.51

Step by Step Solution

1. Step 1: Write the proportion equation
   123,629.78 : 170,630.96 = 72,642.51 : x
2. Step 2: Convert to fraction form
   123,629.78/170,630.96 = 72,642.51/x
3. Step 3: Cross multiply
   123,629.78x = 170,630.96 × 72,642.51
4. Step 4: Simplify right side
   123,629.78x = 12,395,060,854.90
5. Step 5: Solve for x
   x = 12,395,060,854.90/123,629.78
6. Step 6: Final answer
   x = 100,259.51