Finding the Fourth Proportional to 116,978.40, 161,240.58 and 91,439.64

Step by Step Solution

1. Step 1: Write the proportion equation
   116,978.40 : 161,240.58 = 91,439.64 : x
2. Step 2: Convert to fraction form
   116,978.40/161,240.58 = 91,439.64/x
3. Step 3: Cross multiply
   116,978.40x = 161,240.58 × 91,439.64
4. Step 4: Simplify right side
   116,978.40x = 14,743,780,588.59
5. Step 5: Solve for x
   x = 14,743,780,588.59/116,978.40
6. Step 6: Final answer
   x = 126,038.49