Finding the Fourth Proportional to 112,872.64, 155,771.52 and 65,128

Step by Step Solution

1. Step 1: Write the proportion equation
   112,872.64 : 155,771.52 = 65,128 : x
2. Step 2: Convert to fraction form
   112,872.64/155,771.52 = 65,128/x
3. Step 3: Cross multiply
   112,872.64x = 155,771.52 × 65,128
4. Step 4: Simplify right side
   112,872.64x = 10,145,087,554.56
5. Step 5: Solve for x
   x = 10,145,087,554.56/112,872.64
6. Step 6: Final answer
   x = 89,880.84