Finding the Fourth Proportional to 105,099.30, 157,418.55 and 91,275.30

Step by Step Solution

1. Step 1: Write the proportion equation
   105,099.30 : 157,418.55 = 91,275.30 : x
2. Step 2: Convert to fraction form
   105,099.30/157,418.55 = 91,275.30/x
3. Step 3: Cross multiply
   105,099.30x = 157,418.55 × 91,275.30
4. Step 4: Simplify right side
   105,099.30x = 14,368,425,376.82
5. Step 5: Solve for x
   x = 14,368,425,376.82/105,099.30
6. Step 6: Final answer
   x = 136,712.86