Finding the Fourth Proportional to 104,643.72, 156,965.40 and 86,100.72

Step by Step Solution

1. Step 1: Write the proportion equation
   104,643.72 : 156,965.40 = 86,100.72 : x
2. Step 2: Convert to fraction form
   104,643.72/156,965.40 = 86,100.72/x
3. Step 3: Cross multiply
   104,643.72x = 156,965.40 × 86,100.72
4. Step 4: Simplify right side
   104,643.72x = 13,514,833,955.09
5. Step 5: Solve for x
   x = 13,514,833,955.09/104,643.72
6. Step 6: Final answer
   x = 129,150.93