Finding the Fourth Proportional to 139,901.40, 209,900.70 and 61,072.20

Step by Step Solution

1. Step 1: Write the proportion equation
   139,901.40 : 209,900.70 = 61,072.20 : x
2. Step 2: Convert to fraction form
   139,901.40/209,900.70 = 61,072.20/x
3. Step 3: Cross multiply
   139,901.40x = 209,900.70 × 61,072.20
4. Step 4: Simplify right side
   139,901.40x = 12,819,097,530.54
5. Step 5: Solve for x
   x = 12,819,097,530.54/139,901.40
6. Step 6: Final answer
   x = 91,629.52