Finding the Fourth Proportional to 139,172.42, 208,796.30 and 99,241.85

Step by Step Solution

1. Step 1: Write the proportion equation
   139,172.42 : 208,796.30 = 99,241.85 : x
2. Step 2: Convert to fraction form
   139,172.42/208,796.30 = 99,241.85/x
3. Step 3: Cross multiply
   139,172.42x = 208,796.30 × 99,241.85
4. Step 4: Simplify right side
   139,172.42x = 20,721,330,588.95
5. Step 5: Solve for x
   x = 20,721,330,588.95/139,172.42
6. Step 6: Final answer
   x = 148,889.63