Finding the Fourth Proportional to 103,858.78, 143,321.72 and 65,638.84

Step by Step Solution

1. Step 1: Write the proportion equation
   103,858.78 : 143,321.72 = 65,638.84 : x
2. Step 2: Convert to fraction form
   103,858.78/143,321.72 = 65,638.84/x
3. Step 3: Cross multiply
   103,858.78x = 143,321.72 × 65,638.84
4. Step 4: Simplify right side
   103,858.78x = 9,407,471,447.60
5. Step 5: Solve for x
   x = 9,407,471,447.60/103,858.78
6. Step 6: Final answer
   x = 90,579.45