Finding the Fourth Proportional to 139,748.64, 209,709.12 and 89,860.56

Step by Step Solution

1. Step 1: Write the proportion equation
   139,748.64 : 209,709.12 = 89,860.56 : x
2. Step 2: Convert to fraction form
   139,748.64/209,709.12 = 89,860.56/x
3. Step 3: Cross multiply
   139,748.64x = 209,709.12 × 89,860.56
4. Step 4: Simplify right side
   139,748.64x = 18,844,578,960.31
5. Step 5: Solve for x
   x = 18,844,578,960.31/139,748.64
6. Step 6: Final answer
   x = 134,846.24