Finding the Fourth Proportional to 139,839.30, 209,525.67 and 98,211.78

Step by Step Solution

1. Step 1: Write the proportion equation
   139,839.30 : 209,525.67 = 98,211.78 : x
2. Step 2: Convert to fraction form
   139,839.30/209,525.67 = 98,211.78/x
3. Step 3: Cross multiply
   139,839.30x = 209,525.67 × 98,211.78
4. Step 4: Simplify right side
   139,839.30x = 20,577,889,006.39
5. Step 5: Solve for x
   x = 20,577,889,006.39/139,839.30
6. Step 6: Final answer
   x = 147,153.83